We acknowledge the scientific and technical assistance of the INGM Imaging Facility, in particular, C. Cordiglieri and A. Fasciani, and the INGM FACS sorting facility in particular M.C Crosti (Istituto Nazionale di Genetica Molecolare &#39;Romeo ed Enrica Invernizzi&#39; (INGM), Milan, Italy). We acknowledge M. Giannaccari for his technical informatic support. This work was funded by the following grants: Fondazione Cariplo (Bando Giovani, grant nr 2018-0321) and Fondazione AIRC (grant nr MFAG 29165) to F.M. Ricerca Finalizzata, (grant nr GR-2018-12365280), Fondazione AIRC (grant nr 2022 27066), Fondazione Cariplo (grant nr 2019-3416), Fondazione Regionale per la Ricerca Biomedica (FRRB CP2_12/2018,) Piano Nazionale di Ripresa e Resilienza (PNRR) (grant nr G43C22002620007) and Progetti di Rilevante Interesse Nazionale (PRIN) (grant nr 2022PKF9S) to B.B.

The use of human samples for research purposes was approved by the Ethics Committees of the Fondazione Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) C&#224; Granda Ospedale Maggiore Policlinico (Milan), and informed consent was obtained from all subjects (authorization numbers: 708_2020). The protocol is organized into three primary sections: immunofluorescence execution, image acquisition, and image analysis. On average, it necessitates 4 working days to be completed (Figure 1).
1. Immunofluorescence preparation
NOTE: This immunofluorescence protocol can be easily customized for various cell types and protein targets by adjusting the fixation and permeabilization conditions. Immunofluorescence preparation typically takes less than 3 days to be completed, with the duration of primary antibody incubation varying based on antibody quality and the target protein (Figure 1).
<ol>
	<li>Sample preparation
	<ol>
		<li>Isolate human peripheral blood mononuclear cells (PBMCs) through a density gradient centrifugation via a medium of approximately 1.077 g/mL density according to the manufacturer&#39;s instructions (Table of Materials).</li>
		<li>Isolate CD4+ T cells from PBMCs with magnetic beads, following the manufacturer&#39;s instructions (Table of Materials).</li>
		<li>Stain cells with antibodies for CD4, CD45RA, and CD45RO (Table of Materials) and proceed with FACS-sorting of na&#239;ve CD4+ T cells as CD4+/CD45RA+/CD45RO- cells, as described elsewhere29,30. 
		NOTE: See the Table of Materials for specifications of the FACS sorter used in this protocol.</li>
		<li>Induce the differentiation of na&#239;ve CD4+ T cells into T helper 1 (TH1 CD4+ cells) as described in 29. Briefly, culture 1.5 x 106 cells/mL of FACS-sorted na&#239;ve CD4+ T cells in TH1 medium stimulating them with anti-CD3/anti-CD28 magnetic beads at a 1:1 ratio. Count the cells and split them when they reach 1.5 &#215; 106 cells/mL every 2-3 days (see Table 1 for TH1 medium composition).</li>
		<li>Evaluate the secretion of effector function cytokines after 7 days of differentiation, as described in 29.</li>
	</ol>
	</li>
	<li>Cell fixation and permeabilization 
	NOTE: All these procedures were described in 30,31 with minor adaptations.
	<ol>
		<li>To ensure optimal cell adhesion, treat glass coverslips (10 mm, thickness 1.5 H) with coating solution (Table 1) as follows:
		<ol>
			<li>Clean the glass coverslips by initially washing them with distilled water (ddH2O), followed by a rinse with 70% ethanol (EtOH), and allowing them to air dry.</li>
			<li>Place the washed coverslips in a 24-multiwell plate for steps 1.2.1.3-1.3.</li>
			<li>Apply a drop of 200 &#181;L of coating solution onto the glass coverslip. After 5 min, remove the drop and let it air dry.</li>
			<li>Wash the coverslips by applying a drop of 200 &#181;L of ddH2O. After 5 min, remove the drop and air dry.</li>
			<li>Repeat 3 x steps 1.2.1.3-1.2.1.4.</li>
		</ol>
		</li>
		<li>Resuspend na&#239;ve CD4+ T cells and TH1 CD4+ cells in 1x phosphate-buffered saline (PBS) at 2 &#215; 106 cells/mL concentration. 
		NOTE: The indicated&#160;concentration is advised specifically for small cells such as human primary T lymphocytes. For adherent cells, glass coating treatment is unnecessary. Instead, proceed directly with growing the cells on the glass surface using the appropriate cell culture medium.</li>
		<li>Apply a 200 &#181;L drop of the cell suspension onto the glass cover slip. Allow the cells to seed at room temperature (RT) for 30 min; then, remove the drop.</li>
		<li>Fix the cells with freshly filtered 3% paraformaldehyde (PFA solution, Table 1) for 10 min at RT.</li>
		<li>Wash the glass coverslip with TPBS (Table 1) for 3 x 5 min at RT.</li>
		<li>Remove TPBS and add permeabilization solution (Table 1) for 10 min at RT.</li>
		<li>Discard the permeabilization solution and incubate the sample in storage solution (Table 1) from 1 h to overnight (ON) at 4 &#176;C. 
		NOTE: At this stage, the protocol can be safely halted, and the glass cover slips can be preserved in storage solution in a 24-multiwell plate for 3-4 weeks.</li>
	</ol>
	</li>
	<li>Immunofluorescence
	<ol>
		<li>(Optional) Remove the coverslip from the 24-multiwell plate and rapidly freeze on dry ice for 30 s, thaw at RT, and then wash the glass coverslip in a prefilled well with storage solution.</li>
		<li>(Optional) Repeat 3 x step 1.3.1.</li>
		<li>Wash in permeabilization solution for 5 min at RT. Next, wash for 2 x 5 min with TPBS at RT.</li>
		<li>Incubate in 0.1 N HCl for 12 min at RT.</li>
		<li>Perform two quick washes in 1x PBS. 
		NOTE: The specified cell permeabilization conditions, including freeze and thaw steps and HCl treatment, are optimal for staining nuclear components in cells characterized by densely packed chromatin. However, when dealing with cells characterized by less compacted chromatin, it is advisable to reduce or avoid these steps. Additionally, for targeting cytoplasmic components, consider reducing or eliminating HCl treatment.</li>
		<li>Incubate the cells with primary antibody (BRD4, 1:500, or SUZ12, 1:100) diluted in antibody dilution buffer (Table 1) (200 &#181;L for each glass coverslip) ON at 4 &#176;C. 
		NOTE: Immunofluorescence can be performed by multiplexing more than one primary antibody depending on experimental needs, secondary antibodies, and detection systems.</li>
		<li>Wash 3 x 5 min with PBS-T (Table 1) at RT with mild shaking.</li>
		<li>Incubate the cells with secondary antibody diluted in antibody dilution buffer (200 &#181;L for each glass coverslip) for 1 h at RT. 
		NOTE: Choose the secondary antibody that best suits the experimental needs and the available detection systems. Ensure that each secondary antibody targets the species from which the primary antibody is derived. Additionally, select fluorophores that are compatible with the microscope&#39;s filters and light source. It is crucial to avoid spectral overlap between the chosen fluorophore and the emission spectrum of the nuclear stain.</li>
		<li>Wash 3 x 5 min with PBS-T at RT with mild shaking.</li>
		<li>Stain with 1 ng/mL of 4&#39;,6-diamidino-2-phenylindole (DAPI) diluted in 1x PBS for 5 min at RT. 
		NOTE: Alternative dyes can be used for nuclear staining as long as they do not overlap with the emission spectrum of secondary antibodies.</li>
		<li>Perform several quick washes in 1x PBS.</li>
		<li>Mount the glass coverslip on a microscopy slide with antifade mounting media.</li>
	</ol>
	</li>
</ol>
2. Image acquisition
NOTE: The duration of image acquisition depends on the instrument and selected settings.
<ol>
	<li>Confocal microscope acquisition
	<ol>
		<li>Capture 3D images using a confocal microscope, setting a step size of 0.25 &#181;m in z and pixel size of 0.1-0.2 &#181;m. 
		NOTE: To achieve optimal light diffraction-limited resolution with our 63x 1.4 NA Oil objective, we set the pinhole size at 0.8 AU, 2x line average, and frame size 1024 &#215; 1024 pixels. The excitation laser as well as the channel acquisition sequence were selected deliberately to prevent interference or crosstalk between the fluorophores being used. However, the adjustment of parameters should be tailored to the specific microscope and specimen characteristics. See the Table of Materials for specifications of the confocal microscope used in this protocol.</li>
		<li>Acquire a consistent number of random fields to encompass approximately 50 cells per biological replicate.</li>
	</ol>
	</li>
</ol>
3. Image analysis
<ol>
	<li>Software installation
	<ol>
		<li>Download and install the last available version of Fiji from the official Fiji Download page (https://imagej.net/software/fiji/downloads).</li>
		<li>Install 3D Suite either via the Fiji update site or manually following the instructions on the 3D Suite website (https://mcib3d.frama.io/3d-suite-imagej/#download).</li>
		<li>Install GDSC (FindFoci) either via the Fiji update site or manually by following the instructions on the GitHub repository (https://github.com/aherbert/gdsc).&#160;</li>
	</ol>
	</li>
	<li>TIFF conversion
	<ol>
		<li>Download the &#34;convert_to_TIFF.py&#34; script (Supplemental File 1).</li>
		<li>Drag and drop the script on Fiji and run the code.</li>
		<li>In the panel that appears, browse to the path where the experiment is stored. The subfolder containing the converted TIFF files is created in the same experiment folder.</li>
	</ol>
	</li>
	<li>Initialize settings on 3D Manager.
	<ol>
		<li>Open the 3D Manager option panel by clicking on Plugins | 3DSuite | 3D Manager Options.</li>
		<li>Within the 3D Manager option window, select the checkboxes corresponding to the following measurements: Volume (unit), Mean Gray Value, Bounding box (pix), Std Dev Gray Value, Centroid (pix), and Centroid (unit).</li>
		<li>Tick the following options: Exclude objects on edges XY and Exclude objects on edges Z and click OK. 
		NOTE: This step needs to be done only once to initially configure the metrics that will be stored in the spatial and quantitative information files. The selected metrics are essential for ensuring proper pipeline functioning. Optional additional metrics can be included in this step, as further described in the Discussion section.</li>
	</ol>
	</li>
	<li>Set parameters on FindFoci GUI. 
	NOTE: This step needs to be done only once to configure the semi-automated pipeline with optimal parameters, which will then be incorporated into the scripts.
	<ol>
		<li>Open the test image. Duplicate the protein channel, including the stack (Ctrl + Shift + D), check the hyperstack checkbox, and specify the appropriate channel number within the Channels (c) box, and rename it accordingly.</li>
		<li>Launch the Fiji macro recorder by navigating to Plugins | Macros | Record.</li>
		<li>Open the FindFoci plugin (click on Plugins | GDSC | FindFoci | FindFoci GUI) and select the image to be analyzed from the &#34;Image&#34; dropdown menu.</li>
		<li>Set the parameters as follows (Figure 2A): Gaussian blur = 1.5; background method = SD above mean; background param = 9; search method = fraction of peak - background; search param = 0.7; peak method = relative above background; peak param = 0.2; minimum size = 5; max peaks = 1,000,000. 
		NOTE: The indicated parameters have been selected based on our case studies and may not be suitable for other staining procedures.</li>
		<li>To enhance foci identification, adjust the following parameters:
		<ol>
			<li>Gaussian blur defines the extent of smoothening to better segment foci. Keep it close to the foci diameter (pixel).</li>
			<li>Background param&#160;sets a threshold to distinguish the background from the foci signal. Increase the values to impose more stringent thresholds.</li>
			<li>Search param defines the percentage of fluorescence from the peak that is included in signal recognition. Decrease the values to include areas farther away from the fluorescence peak.</li>
			<li>Peak param&#160;determines the degree to which two signal peaks are considered continuous or separated. Decreasing the value will result in the separation of peaks.</li>
			<li>Max peaks&#160;specifies the maximum number of foci identifiable. Set high numbers to include all foci in the image.</li>
		</ol>
		</li>
		<li>Run FindFoci and copy the string that appears in the recorder window (Step 3.4.2, Figure 2B) that contains the selected parameters, excluding the quotation marks. For further information related to the settings, refer to the plugin manual instruction 22.</li>
	</ol>
	</li>
	<li>Nuclear protein quantification pipeline
	<ol>
		<li>Download the script &#34;nuclear_prot_q.py&#34; (Supplemental File 2).</li>
		<li>Drag and drop the script on Fiji and click run to execute the code.</li>
		<li>Follow the instructions within the displayed dialog box to process the images.
		<ol>
			<li>Nucleus channel: enter the number corresponding to the channel of DAPI (or any nuclear staining).</li>
			<li>Nucleus Gaussian Blur: enter the value of sigma needed to blur the image for segmentation. 
			NOTE: Maintain this parameter closer to the nucleus diameter (i.e., 5-6 &#181;m). Higher sigma values are indicated for inhomogeneous staining.</li>
			<li>Protein channel: enter the number corresponding to the channel of the staining of interest.</li>
			<li>FindFoci Parameter:&#160;paste the string obtained from the macro recording step in passage 3.4.6 (Figure 2B).</li>
			<li>(Optional) Quality control: check the quality of the segmented nuclei. This will pause the script and allow manual checking of each generated nuclear region of interest (ROI).</li>
			<li>Select an image directory: click the Browse button to navigate to the folder containing the TIFF&#160;files to be analyzed.</li>
		</ol>
		</li>
		<li>Once all boxes are compiled, click OK to continue the execution.</li>
		<li>If a nucleus is not correctly segmented and fails to meet quality requirements, delete or modify it as indicated in Figure 2C.
		<ol>
			<li>Check the ROI list in the ROIManager3D window; if the list is empty, select the merge window and click Quantify 3D to refresh the manager. Then, close the Quantify 3D result table. Select the nuclei channel and click Live-ROI to ON.</li>
			<li>Select the ROI belonging to the same nucleus and press Merge or press Delete in the case of undesired nuclei.</li>
			<li>Click select all and proceed with the analysis by clicking OK in the Mask check window.</li>
			<li>For results, look in the Quantification folder within the file path indicated in step 3.5.3.6, containing a txt file with records of the parameter used for the analysis.</li>
		</ol>
		</li>
	</ol>
	</li>
	<li>Pipeline on Google Colab
	<ol>
		<li>Download the &#34;final_nuclear_protein_metrics.ipynb&#34; notebook (Supplemental File 3).</li>
		<li>Open the notebook on Google Colab (https://colab.research.google.com/).</li>
		<li>Upload all the folders containing the .csv files of each image field into a folder of preference in Google Drive.</li>
		<li>Indicate in the notebook the path of the folder where the result subfolders are stored and run all cells. When the code has finished compiling, the final spreadsheet file containing all the compiled data is created in the same folder where the .csv files were uploaded.</li>
	</ol>
	</li>
</ol>

Analysis Workflow of Nuclear Protein Staining in Human Primary Cells

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M., Hoffmann, E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=FindFoci:+a+focus+detection+algorithm+with+automated+parameter+training+that+closely+matches+human+assignments,+reduces+human+inconsistencies+and+increases+speed+of+analysis.">FindFoci: a focus detection algorithm with automated parameter training that closely matches human assignments, reduces human inconsistencies and increases speed of analysis.</a> PLoS One. 9 (12), e114749 (2014).</li><li>Ollion, J., Cochennec, J., Loll, F., Escude, C., Boudier, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=TANGO:+a+generic+tool+for+high-throughput+3D+image+analysis+for+studying+nuclear+organization.">TANGO: a generic tool for high-throughput 3D image analysis for studying nuclear organization.</a> Bioinformatics. 29 (14), 1840-1841 (2013).</li><li>Sabari, B. R., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Coactivator+condensation+at+super-enhancers+links+phase+separation+and+gene+control.">Coactivator condensation at super-enhancers links phase separation and gene control.</a> Science. 361 (6400), 3958 (2018).</li><li>Jang, M. K., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+bromodomain+protein+Brd4+is+a+positive+regulatory+component+of+P-TEFb+and+stimulates+RNA+polymerase+II-dependent+transcription.">The bromodomain protein Brd4 is a positive regulatory component of P-TEFb and stimulates RNA polymerase II-dependent transcription.</a> Mol Cell. 19 (4), 523-534 (2005).</li><li>Pasini, D., Bracken, A. P., Jensen, M. R., Denchi, E. L., Helin, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Suz12+is+essential+for+mouse+development+and+for+EZH2+histone+methyltransferase+activity.">Suz12 is essential for mouse development and for EZH2 histone methyltransferase activity.</a> EMBO J. 23 (20), 4061-4071 (2004).</li><li>Margueron, R., Reinberg, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+Polycomb+complex+PRC2+and+its+mark+in+life.">The Polycomb complex PRC2 and its mark in life.</a> Nature. 469 (7330), 343-349 (2011).</li><li>Peng, Z., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Brd4+regulates+the+homeostasis+of+CD8(+)+T-lymphocytes+and+their+proliferation+in+response+to+antigen+stimulation.">Brd4 regulates the homeostasis of CD8(+) T-lymphocytes and their proliferation in response to antigen stimulation.</a> Front Immunol. 12, 728082 (2021).</li><li>Marasca, F., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=LINE1+are+spliced+in+non-canonical+transcript+variants+to+regulate+T+cell+quiescence+and+exhaustion.">LINE1 are spliced in non-canonical transcript variants to regulate T cell quiescence and exhaustion.</a> Nat Genet. 54 (2), 180-193 (2022).</li><li>Marasca, F., Cortesi, A., Bodega, B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=3D+COMBO+chrRNA-DNA-ImmunoFISH.">3D COMBO chrRNA-DNA-ImmunoFISH.</a> Methods Mol Biol. 2157, 281-297 (2021).</li><li>Marasca, F., Cortesi, A., Manganaro, L., Bodega, B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=3D+Multicolor+DNA+FISH+tool+to+study+nuclear+architecture+in+human+primary+cells.">3D Multicolor DNA FISH tool to study nuclear architecture in human primary cells.</a> J Vis Exp. (155), (2020).</li><li>Jakob, B., Splinter, J., Durante, M., Taucher-Scholz, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Live+cell+microscopy+analysis+of+radiation-induced+DNA+double-strand+break+motion.">Live cell microscopy analysis of radiation-induced DNA double-strand break motion.</a> Proc Natl Acad Sci U S A. 106 (9), 3172-3177 (2009).</li></ol>

R.V. has a scientific collaboration with the startup T-One Therapeutics Srl; B.B. and F.M. are co-founders of the startup T-One Therapeutics Srl; E.P. is currently employed by T-One Therapeutics Srl; all the other authors declare they have no competing interests.

In this study, we present a method for performing immunofluorescence experiments on nuclear proteins in human T lymphocytes. This method offers flexibility for use with various cell types through minor modifications in fixation and permeabilization steps, as described previously30,31. 
Our imaging workflow builds upon established techniques outlined in the literature, specifically FindFoci and 3D Suite22,</...

The organization of the eukaryotic genome is governed by multiple layers of epigenetic modifications1, coordinating several nuclear functions that can occur within specialized compartments called nuclear bodies or condensates2. Within these structures, processes such as transcription initiation3, RNA processing4,5,6, DNA repair7,8, ribosome biogenesis9,10,11, and heterochromatin regulation12,13 take place. The regulation of nuclear bodies adjusts over both spatial and temporal dimensions to accommodate cellular requirements, guided by principles of phase separation14,15. Consequently, these bodies function as transient factories where functional components assemble and disassemble, undergoing changes in size and spatial distribution. Hence, understanding the characteristics of nuclear proteins by microscopy, including their propensity to form bodies and their spatial arrangement in different cellular conditions, offers valuable insights into their functional roles. Fluorescence microscopy is a widely used method for studying nuclear proteins, allowing their detection through fluorescent antibodies or directly expressing targets with a fluorescent protein reporter16,17.
In this context, nuclear bodies appear as bright foci or puncta, with a notable degree of sphericity, making them easily distinguishable from the surrounding environment16,18. Super-resolution techniques like STORM and PALM, by providing improved resolution (up to 10 nm)19, enable more precise characterization of the structure and composition of specific condensates20. However, their accessibility is limited by equipment expenses and the specialized skills needed for data analysis. Therefore, confocal microscopy remains popular due to its favorable balance between resolution and wider usage. Such popularity is facilitated by the inherent removal of out-of-focus light, which diminishes the requirement for extensive post-processing procedures for accurate segmentation, its widespread availability in research institutes, its effective acquisition time, and sample preparation that is typically efficient. However, accurately measuring protein distribution, assembly, or diffusion using immunofluorescence assays across diverse cellular conditions poses challenges, as many existing methods lack guidance on selecting suitable parameters for proteins with varying distribution patterns21. Moreover, handling the resulting large data volume can be daunting for users with limited experience in data analysis, potentially compromising the biological significance of the results.
To address these challenges, we introduce a detailed step-by-step protocol for immunofluorescence preparation and data analysis, aiming to provide an unbiased method for quantifying protein staining with various organization patterns (Figure 1). This semi-automated pipeline is designed for users with limited expertise in computational and imaging analysis. It combines the functionalities of two established Fiji plugins: FindFoci22 and 3D suite23. By integrating the precise foci identification capability of FindFoci with the object identification and segmentation features in 3D space offered by 3D suite, our approach generates two CSV files per channel for each field of acquisition. These files contain complementary information that facilitates the calculation of metrics suitable for various types of signal distribution, such as the count of foci per cell, the distance of foci from the nuclear centroid, and the inhomogeneity coefficient (IC), which we have introduced for diffuse protein staining. In addition, we acknowledge that data extrapolation can be time-consuming for users with limited data handling skills. To streamline this process, we provide a Python script that automatically compiles all collected measurements into a single file for each experiment. Users can execute this script without the need to install any programming language software. We provide an executable code on Google Colab, a cloud-based platform that allows the writing of Python scripts directly in the browser. This ensures that our method is intuitive and readily accessible for immediate use.
We demonstrate the effectiveness of our protocol in analyzing and quantifying alterations in signal distribution of two nuclear proteins: Bromodomain-containing protein 4 (BRD4) and Suppressor of zeste-12 (SUZ12). BRD4 is a well-documented coactivator protein within the Mediator complex known to form condensates associated with polymerase II-dependent transcriptional initiation24,25. SUZ12 is a protein component of the Polycomb Repressive Complex 2 (PRC2) responsible for regulating the deposition of H3K27me3 histone modification26,27. These proteins exhibit different patterns within two distinct cell types: freshly isolated human CD4+ na&#239;ve T cells, which are quiescent and exhibit slow rates of transcriptional activity, and in vitro differentiated TH1 CD4+ cells, which are specialized, proliferating effector cells showing increased transcription28.

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>1.5 mL Safe-Lock Tubes</td>
			<td>Eppendord</td>
			<td>#0030121503</td>
			<td>Protocol section 1</td>
		</tr>
		<tr>
			<td>10 mL Serological pipettes</td>
			<td>VWR</td>
			<td>#612-3700</td>
			<td>Protocol section 1</td>
		</tr>
		<tr>
			<td>20 &#181;L barrier pipette tip</td>
			<td>Thermo Scientific</td>
			<td>#2149P-HR</td>
			<td>Protocol section 1</td>
		</tr>
		<tr>
			<td>50 mL Polypropylene Conical Tube</td>
			<td>Falcon</td>
			<td>#352070</td>
			<td>Protocol section 1</td>
		</tr>
		<tr>
			<td>200 &#181;L barrier pipette tip</td>
			<td>Thermo Scientific</td>
			<td>#2069-HR</td>
			<td>Protocol section 1</td>
		</tr>
		<tr>
			<td>antifade solution - ProlongGlass - mountingmedia</td>
			<td>Invitrogen</td>
			<td>#P36984</td>
			<td>Step 1.3.12</td>
		</tr>
		<tr>
			<td>BSA (Bovine Serum Albumin)</td>
			<td>Sigma</td>
			<td>#A7030</td>
			<td>Step 1.3.6., 1.3.8.</td>
		</tr>
		<tr>
			<td>CD4+ T Cell Isolation Kit</td>
			<td>Miltenyi Biotec</td>
			<td>#130-096-533</td>
			<td>Step 1.1.2.</td>
		</tr>
		<tr>
			<td>DAPI (4,6-diamidino-2-phenylindole)</td>
			<td>Invitrogen</td>
			<td>Cat#D1306</td>
			<td>Step 1.3.10.</td>
		</tr>
		<tr>
			<td>Dry ice</td>
			<td></td>
			<td></td>
			<td>Step 1.3.1.</td>
		</tr>
		<tr>
			<td>Dynabeads Human T-activator anti-CD3/anti-CD28 bead</td>
			<td>Life Technologies</td>
			<td>#1131D</td>
			<td>magnetic beads step 1.1.4.</td>
		</tr>
		<tr>
			<td>EtOH</td>
			<td>Carlo Erba</td>
			<td>#4146320</td>
			<td>Step 1.2.1.1.</td>
		</tr>
		<tr>
			<td>FACSAria SORP</td>
			<td>BD Bioscences</td>
			<td></td>
			<td>Step 1.1.3. Equipped with BD FACSDiva Software version 8.0.3</td>
		</tr>
		<tr>
			<td>FBS (Fetal Bovine Serum)</td>
			<td>Life Technologies</td>
			<td>#10270106</td>
			<td>Step 1.1.4</td>
		</tr>
		<tr>
			<td>FICOLL PAQUE PLUS</td>
			<td>Euroclone</td>
			<td>GEH17144003F32</td>
			<td>Step 1.1.1.</td>
		</tr>
		<tr>
			<td>FIJI Version 2.14.0</td>
			<td>-</td>
			<td>-</td>
			<td>Protocol section 3</td>
		</tr>
		<tr>
			<td>Glass coverslip (10 mm, thickness 1.5 H)</td>
			<td>Electron Microscopy Sciences</td>
			<td>#72298-13</td>
			<td>Step 1.2.1.</td>
		</tr>
		<tr>
			<td>Glycerol</td>
			<td>Sigma</td>
			<td>#G5516</td>
			<td>Step 1.2.7-1.3.1.</td>
		</tr>
		<tr>
			<td>Goat anti-Rabbit AF568 secondary antibody</td>
			<td>Invitrogen</td>
			<td>A11036</td>
			<td>Step 1.3.8.</td>
		</tr>
		<tr>
			<td>HCl</td>
			<td>Sigma</td>
			<td>#320331</td>
			<td>Step 1.3.4.</td>
		</tr>
		<tr>
			<td>human neutralizing anti-IL-4</td>
			<td>Miltenyi Biotec</td>
			<td>Cat#130-095-753</td>
			<td>Step 1.1.4.</td>
		</tr>
		<tr>
			<td>human recombinant IL-12</td>
			<td>Miltenyi Biotec</td>
			<td>Cat#130-096-704</td>
			<td>Step 1.1.4.</td>
		</tr>
		<tr>
			<td>human recombinant IL-2</td>
			<td>Miltenyi Biotec</td>
			<td>Cat#130-097-744</td>
			<td>Step 1.1.4.</td>
		</tr>
		<tr>
			<td>Leica TCS SP5 Confocal microscope</td>
			<td>Leica Microsystems</td>
			<td>-</td>
			<td>Protocol section 2, Equipped with HCX PL APO 63x, 1.40 NA oil immersion objective, with an additional 3x zoom. Pinhole size : 0.8 AU. Line average 2&#215;. Frame size 1024&#215;1024 pixel.</td>
		</tr>
		<tr>
			<td>MEM Non-Essential Amino Acids Solution</td>
			<td>Life Technologies</td>
			<td>#11140035</td>
			<td>Step 1.1.4.</td>
		</tr>
		<tr>
			<td>Microscope Slides</td>
			<td>VWR</td>
			<td>#631-1552</td>
			<td>Step 1.3.12.</td>
		</tr>
		<tr>
			<td>Mouse monoclonal anti-Human CD4 APC-Cy7 (RPA-T4 clone)</td>
			<td>BD Bioscience</td>
			<td>#557871</td>
			<td>Step 1.1.3.</td>
		</tr>
		<tr>
			<td>Mouse monoclonal anti-Human CD45RA PECy5 (5H9 clone)</td>
			<td>BD Bioscience</td>
			<td>#552888</td>
			<td>Step 1.1.3.</td>
		</tr>
		<tr>
			<td>Mouse monoclonal anti-Human CD45RO APC (UCHL1 clone)</td>
			<td>Miltenyi Biotec</td>
			<td>#130-113-546</td>
			<td>Step 1.1.3.</td>
		</tr>
		<tr>
			<td>Multiwell 24 well</td>
			<td>Falcon</td>
			<td>#353047</td>
			<td>Protocol section 1</td>
		</tr>
		<tr>
			<td>Normal Goat Serum</td>
			<td>Invitrogen</td>
			<td>PCN5000</td>
			<td>Step 1.3.6., 1.3.8.</td>
		</tr>
		<tr>
			<td>PBS</td>
			<td>Life Technologies</td>
			<td>#14190094</td>
			<td>Protocol section 1</td>
		</tr>
		<tr>
			<td>Penicillin/Streptomycin solution</td>
			<td>Life Technologies</td>
			<td>#15070063</td>
			<td>Step 1.1.4.</td>
		</tr>
		<tr>
			<td>PFA</td>
			<td>Sigma</td>
			<td>#P6148</td>
			<td>Step 1.2.4.</td>
		</tr>
		<tr>
			<td>poly-L-lysine</td>
			<td>Sigma</td>
			<td>#P8920</td>
			<td>1.2.1.</td>
		</tr>
		<tr>
			<td>Primary antibody - BRD4</td>
			<td>Abcam</td>
			<td>#ab128874</td>
			<td>Step 1.3.6.</td>
		</tr>
		<tr>
			<td>Primary antibody - SUZ12</td>
			<td>Cel Signalling</td>
			<td>mAb #3737</td>
			<td>Step 1.3.6.</td>
		</tr>
		<tr>
			<td>RPMI 1640 W/GLUTAMAX-I</td>
			<td>Life Technologies</td>
			<td>#61870010</td>
			<td>Step 1.1.4.</td>
		</tr>
		<tr>
			<td>Sodium Pyruvate</td>
			<td>Life Technologies</td>
			<td>#11360039</td>
			<td>Step 1.1.4.</td>
		</tr>
		<tr>
			<td>Triton X-100</td>
			<td>Sigma</td>
			<td>#T8787</td>
			<td>Step 1.2., 1.3.</td>
		</tr>
		<tr>
			<td>TWEEN 20</td>
			<td>Sigma</td>
			<td>#P9416</td>
			<td>Step 1.3.</td>
		</tr>
		<tr>
			<td>Tweezers</td>
			<td>-</td>
			<td>-</td>
			<td>Protocol section 1</td>
		</tr>
	</tbody>
</table>

a versatile pipeline for analyzing dynamic changes in nuclear bodies in a variety of cell types

Various nuclear processes, such as transcriptional control, occur within discrete structures known as foci that are discernable through the immunofluorescence technique. Investigating the dynamics of these foci under diverse cellular conditions via microscopy yields valuable insights into the molecular mechanisms governing cellular identity and functions. However, performing immunofluorescence assays across different cell types and assessing alterations in the assembly, diffusion, and distribution of these foci present numerous challenges. These challenges encompass complexities in sample preparation, determination of parameters for analyzing imaging data, and management of substantial data volumes. Moreover, existing imaging workflows are often tailored for proficient users, thereby limiting accessibility to a broader audience.
In this study, we introduce an optimized immunofluorescence protocol tailored for investigating nuclear proteins in different human primary T cell types that can be customized for any protein of interest and cell type. Furthermore, we present a method for unbiasedly quantifying protein staining, whether they form distinct foci or exhibit a diffuse nuclear distribution.
Our proposed method offers a comprehensive guide, from cellular staining to analysis, leveraging a semi-automated pipeline developed in Jython and executable in Fiji. Furthermore, we provide a user-friendly Python script to streamline data management, publicly accessible on a Google Colab notebook. Our approach has demonstrated efficacy in yielding highly informative immunofluorescence analyses for proteins with diverse patterns of nuclear organization across different&#160;contexts.

The outlined protocol in this method facilitates the visualization and quantification of alterations in nuclear protein staining within human primary T cells, and it can be customized for diverse cell types and protein targets. As case studies, we conducted and analyzed the staining of BRD4 and SUZ12 in na&#239;ve and TH1 CD4+ cells.
BRD4 displays a well-dotted staining pattern in both quiescent na&#239;ve and differentiated TH1 CD4+...

Author Spotlight: Comprehensive Epigenetic Analysis for Investigating Human Cellular Plasticity and Environmental Adaptation Using Immunofluorescence Assays

This method describes an immunofluorescence protocol and quantification pipeline for evaluating protein distribution with varied nuclear organization patterns in human T lymphocytes. This protocol provides step-by-step guidance, starting from sample preparation and continuing through the execution of semi-automated analysis in Fiji, concluding with data handling by a Google Colab notebook.

A Versatile Pipeline for Analyzing Dynamic Changes in Nuclear Bodies in a Variety of Cell Types

Various nuclear processes, such as transcriptional control, occur within discrete structures known as foci that are discernable through the ...

a-versatile-pipeline-for-analyzing-dynamic-changes-nuclear-bodies

Research

JoVE Journal

Genetics

356 Views.  Istituto Nazionale di Genetica Molecolare "Romeo ed Enrica Invernizzi" (INGM). This method describes an immunofluorescence protocol and quantification pipeline for evaluating protein distribution with varied nuclear organization patterns in human T lymphocytes. This protocol provides step-by-step guidance, starting from sample preparation and continuing through the execution of semi-automated analysis in Fiji, concluding with data handling by a Google Colab notebook.

Video: Author Spotlight: Comprehensive Epigenetic Analysis for Investigating Human Cellular Plasticity and Environmental Adaptation Using Immunofluorescence Assays

Rearing and Double-stranded RNA-mediated Gene Knockdown in the Hide Beetle, Dermestes maculatus

Advances in genomics have raised the possibility of probing biodiversity at an unprecedented scale. However, sequence alone will not be informative without tools to study gene function. The development and sharing of detailed protocols for the establishment of new model systems in laboratories, and for tools to carry out functional studies, is thus crucial for leveraging the power of genomics. Coleoptera (beetles) are the largest clade of insects and occupy virtually all types of habitats on the planet. In addition to providing ideal models for fundamental research, studies of beetles can have impacts on pest control as they are often pests of households, agriculture, and food industries. Detailed protocols for rearing and maintenance of D. maculatus laboratory colonies and for carrying out dsRNA-mediated interference in D. maculatus are presented. Both embryonic and parental RNAi procedures-including apparatus set up, preparation, injection, and post-injection recovery-are described. Methods are also presented for analyzing embryonic phenotypes, including viability, patterning defects in hatched larvae, and cuticle preparations for unhatched larvae. These assays, together with in situ hybridization and immunostaining for molecular markers, make D. maculatus an accessible model system for basic and applied research. They further provide useful information for establishing procedures in other emerging insect model systems.

Rearing and Double-stranded RNA-mediated Gene Knockdown in the Hide Beetle, Dermestes maculatus

Here, we present protocols for rearing an intermediate-germ beetle, Dermestes maculatus (D. maculatus) in the lab. We also share protocols for embryonic and parental RNAi and methods for analyzing embryonic phenotypes to study gene function in this species.

Advances in genomics have raised the possibility of probing biodiversity at an unprecedented scale. However, sequence alone will not be informative ...

Detection of Copy Number Alterations Using Single Cell Sequencing

Detection of genomic changes at single cell resolution is important for characterizing genetic heterogeneity and evolution in normal tissues, cancers, and microbial populations. Traditional methods for assessing genetic heterogeneity have been limited by low resolution, low sensitivity, and/or low specificity. Single cell sequencing has emerged as a powerful tool for detecting genetic heterogeneity with high resolution, high sensitivity and, when appropriately analyzed, high specificity. Here we provide a protocol for the isolation, whole genome amplification, sequencing, and analysis of single cells. Our approach allows for the reliable identification of megabase-scale copy number variants in single cells. However, aspects of this protocol can also be applied to investigate other types of genetic alterations in single cells.

Single cell sequencing is an increasingly popular and accessible tool for addressing genomic changes at high resolution. We provide a protocol that uses single cell sequencing to identify copy number alterations in single cells.

Detection of genomic changes at single cell resolution is important for characterizing genetic heterogeneity and evolution in normal tissues, cancers, and ...

The Nematode Caenorhabditis Elegans - A Versatile In Vivo Model to Study Host-microbe Interactions

We demonstrate a method using Caenorhabditis elegans as a model host to study microbial interaction. Microbes are introduced via the diet making the intestine the primary location for disease. The nematode intestine structurally and functionally mimics mammalian intestines and is transparent making it amenable to microscopic study of colonization. Here we show that pathogens can cause disease and death. We are able to identify microbial mutants that show altered virulence. Its conserved innate response to biotic stresses makes C. elegans an excellent system to probe facets of host innate immune interactions. We show that hosts with mutations in the dual oxidase gene cannot produce reactive oxygen species and are unable to resist microbial insult. We further demonstrate the versatility of the presented survival assay by showing that it can be used to study the effects of inhibitors of microbial growth. This assay may also be used to discover fungal virulence factors as targets for the development of novel antifungal agents, as well as provide an opportunity to further uncover host-microbe interactions. The design of this assay lends itself well to high throughput whole-genome screens, while the ability to cryo-preserve worms for future use makes it a cost-effective and attractive whole animal model to study.

The Nematode Caenorhabditis Elegans - A Versatile In Vivo Model to Study Host-microbe Interactions

Here, we present the nematode Caenorhabditis elegans as a versatile host model to study microbial interaction.

We demonstrate a method using Caenorhabditis elegans as a model host to study microbial interaction. Microbes are introduced via the diet making the ...

CRISPR/Cas9-mediated Targeted Integration In Vivo Using a Homology-mediated End Joining-based Strategy

As a promising genome editing platform, the CRISPR/Cas9 system has great potential for efficient genetic manipulation, especially for targeted integration of transgenes. However, due to the low efficiency of homologous recombination (HR) and various indel mutations of non-homologous end joining (NHEJ)-based strategies in non-dividing cells, in vivo genome editing remains a great challenge. Here, we describe a homology-mediated end joining (HMEJ)-based CRISPR/Cas9 system for efficient in vivo precise targeted integration. In this system, the targeted genome and the donor vector containing homology arms (~800 bp) flanked by single guide RNA (sgRNA) target sequences are cleaved by CRISPR/Cas9. This HMEJ-based strategy achieves efficient transgene integration in mouse zygotes, as well as in hepatocytes in vivo. Moreover, a HMEJ-based strategy offers an efficient approach for correction of fumarylacetoacetate hydrolase (Fah) mutation in the hepatocytes and rescues Fah-deficiency induced liver failure mice. Taken together, focusing on targeted integration, this HMEJ-based strategy provides a promising tool for a variety of applications, including generation of genetically modified animal models and targeted gene therapies.

CRISPR/Cas9-mediated Targeted Integration In Vivo Using a Homology-mediated End Joining-based Strategy

The clustered regularly interspaced short palindromic repeats/CRISPR associated protein 9 (CRISPR/Cas9) system provides a promising tool for genetic engineering, and opens up the possibility of targeted integration of transgenes. We describe a homology-mediated end joining (HMEJ)-based strategy for efficient DNA targeted integration in vivo and targeted gene therapies using CRISPR/Cas9.

As a promising genome editing platform, the CRISPR/Cas9 system has great potential for efficient genetic manipulation, especially for targeted integration ...

Targeted Next-generation Sequencing and Bioinformatics Pipeline to Evaluate Genetic Determinants of Constitutional Disease

Next-generation sequencing (NGS) is quickly revolutionizing how research into the genetic determinants of constitutional disease is performed. The technique is highly efficient with millions of sequencing reads being produced in a short time span and at relatively low cost. Specifically, targeted NGS is able to focus investigations to genomic regions of particular interest based on the disease of study. Not only does this further reduce costs and increase the speed of the process, but it lessens the computational burden that often accompanies NGS. Although targeted NGS is restricted to certain regions of the genome, preventing identification of potential novel loci of interest, it can be an excellent technique when faced with a phenotypically and genetically heterogeneous disease, for which there are previously known genetic associations. Because of the complex nature of the sequencing technique, it is important to closely adhere to protocols and methodologies in order to achieve sequencing reads of high coverage and quality. Further, once sequencing reads are obtained, a sophisticated bioinformatics workflow is utilized to accurately map reads to a reference genome, to call variants, and to ensure the variants pass quality metrics. Variants must also be annotated and curated based on their clinical significance, which can be standardized by applying the American College of Medical Genetics and Genomics Pathogenicity Guidelines. The methods presented herein will display the steps involved in generating and analyzing NGS data from a targeted sequencing panel, using the ONDRISeq neurodegenerative disease panel as a model, to identify variants that may be of clinical significance.

Targeted next-generation sequencing is a time- and cost-efficient approach that is becoming increasingly popular in both disease research and clinical diagnostics. The protocol described here presents the complex workflow required for sequencing and the bioinformatics process used to identify genetic variants that contribute to disease.

Next-generation sequencing (NGS) is quickly revolutionizing how research into the genetic determinants of constitutional disease is performed. The ...

A Rapid and Facile Pipeline for Generating Genomic Point Mutants in C. elegans Using CRISPR/Cas9 Ribonucleoproteins

The clustered regularly interspersed palindromic repeats (CRISPR)-CRISPR-associated protein 9 (Cas9) prokaryotic adaptive immune defense system has been co-opted as a powerful tool for precise eukaryotic genome engineering. Here, we present a rapid and simple method using chimeric single guide RNAs (sgRNA) and CRISPR-Cas9 Ribonucleoproteins (RNPs) for the efficient and precise generation of genomic point mutations in C. elegans. We describe a pipeline for sgRNA target selection, homology-directed repair (HDR) template design, CRISPR-Cas9-RNP complexing and delivery, and a genotyping strategy that enables the robust and rapid identification of correctly edited animals. Our approach not only permits the facile generation and identification of desired genomic point mutant animals, but also facilitates the detection of other complex indel alleles in approximately 4 - 5 days with high efficiency and a reduced screening workload.

A Rapid and Facile Pipeline for Generating Genomic Point Mutants in C. elegans Using CRISPR/Cas9 Ribonucleoproteins

Here, we present a method to engineer the genome of C. elegans using CRISPR-Cas9 ribonucleoproteins and homology dependent repair templates.

The clustered regularly interspersed palindromic repeats (CRISPR)-CRISPR-associated protein 9 (Cas9) prokaryotic adaptive immune defense system has been ...

Endogenous Protein Tagging in Human Induced Pluripotent Stem Cells Using CRISPR/Cas9

A protocol is presented for generating human induced pluripotent stem cells (hiPSCs) that express endogenous proteins fused to in-frame&#160;N- or C-terminal fluorescent tags. The prokaryotic CRISPR/Cas9 system (clustered regularly interspaced short palindromic repeats/CRISPR-associated 9) may be used to introduce large exogenous sequences into genomic loci via homology directed repair (HDR). To achieve the desired knock-in, this protocol employs the ribonucleoprotein (RNP)-based approach where wild type Streptococcus pyogenes Cas9 protein, synthetic 2-part guide RNA (gRNA), and a donor template plasmid are delivered to the cells via electroporation. Putatively edited cells expressing the fluorescently tagged proteins are enriched by fluorescence activated cell sorting (FACS). Clonal lines are then generated and can be analyzed for precise editing outcomes. By introducing the fluorescent tag at the genomic locus of the gene of interest, the resulting subcellular localization and dynamics of the fusion protein can be studied under endogenous regulatory control, a key improvement over conventional overexpression systems. The use of hiPSCs as a model system for gene tagging provides the opportunity to study the tagged proteins in diploid, nontransformed cells. Since hiPSCs can be differentiated into multiple cell types, this approach provides the opportunity to create and study tagged proteins in a variety of isogenic cellular contexts.

Described here is a protocol for tagging endogenously expressed proteins with fluorescent tags in human induced pluripotent stem cells using CRISPR/Cas9. Putatively edited cells are enriched by fluorescence activated cell sorting and clonal cell lines are generated.

A protocol is presented for generating human induced pluripotent stem cells (hiPSCs) that express endogenous proteins fused to in-frame&#160;N- or ...

Using In Vitro and In-cell SHAPE to Investigate Small Molecule Induced Pre-mRNA Structural Changes

In the process of drug development of RNA-targeting small molecules, elucidating the structural changes upon their interactions with target RNA sequences is desired. We herein provide a detailed in vitro and in-cell selective 2&#39;-hydroxyl acylation analyzed by primer extension (SHAPE) protocol to study the RNA structural change in the presence of an experimental drug for spinal muscular atrophy (SMA), survival of motor neuron (SMN)-C2, and in exon 7 of the pre-mRNA of the SMN2 gene. In in vitro SHAPE, an RNA sequence of 140 nucleotides containing SMN2 exon 7 is transcribed by T7 RNA polymerase, folded in the presence of SMN-C2, and subsequently modified by a mild 2&#39;-OH acylation reagent, 2-methylnicotinic acid imidazolide (NAI). This 2&#39;-OH-NAI adduct is further probed by a 32P-labeled primer extension and resolved by polyacrylamide gel electrophoresis (PAGE). Conversely, 2&#39;-OH acylation in in-cell SHAPE takes place in situ with SMN-C2 bound cellular RNA in living cells. The pre-mRNA sequence of exon 7 in the SMN2 gene, along with SHAPE-induced mutations in the primer extension, was then amplified by PCR and subject to next-generation sequencing. Comparing the two methodologies, in vitro SHAPE is a more cost-effective method and does not require computational power to visualize results. However, the in vitro SHAPE-derived RNA model sometimes deviates from the secondary structure in a cellular context, likely due to the loss of all interactions with RNA-binding proteins. In-cell SHAPE does not need a radioactive material workplace and yields a more accurate RNA secondary structure in the cellular context. Furthermore, in-cell SHAPE is usually applicable for a larger range of RNA sequences (~1,000 nucleotides) by utilizing next-generation sequencing, compared to in vitro SHAPE (~200 nucleotides) that usually relies on PAGE analysis. In case of exon 7 in SMN2 pre-mRNA, the in vitro and in-cell SHAPE derived RNA models are similar to each other.

Detailed protocols for both in vitro and in-cell selective 2&#39;-hydroxyl acylation analyzed by primer extension (SHAPE) experiments to determine the secondary structure of pre-mRNA sequences of interest in the presence of an RNA-targeting small molecule are presented in this article.

In the process of drug development of RNA-targeting small molecules, elucidating the structural changes upon their interactions with target RNA sequences ...

Characterizing Histone Post-translational Modification Alterations in Yeast Neurodegenerative Proteinopathy Models

Neurodegenerative diseases, such as amyotrophic lateral sclerosis (ALS) and Parkinson&#39;s disease (PD), cause the loss of hundreds of thousands of lives each year. Effective treatment options able to halt disease progression are lacking. Despite the extensive sequencing efforts in large patient populations, the majority of ALS and PD cases remain unexplained by genetic mutations alone. Epigenetics mechanisms, such as the post-translational modification of histone proteins, may be involved in neurodegenerative disease etiology and progression and lead to new targets for pharmaceutical intervention. Mammalian in vivo and in vitro models of ALS and PD are costly and often require prolonged and laborious experimental protocols. Here, we outline a practical, fast, and cost-effective approach to determining genome-wide alterations in histone modification levels using Saccharomyces cerevisiae as a model system. This protocol allows for comprehensive investigations into epigenetic changes connected to neurodegenerative proteinopathies that corroborate previous findings in different model systems while significantly expanding our knowledge of the neurodegenerative disease epigenome.

This protocol outlines experimental procedures to characterize genome-wide changes in the levels of histone post-translational modifications (PTM) occurring in connection with the overexpression of proteins associated with ALS and Parkinson&#39;s disease in Saccharomyces cerevisiae models. After SDS-PAGE separation, individual histone PTM levels are detected with modification-specific antibodies via Western blotting.

Neurodegenerative diseases, such as amyotrophic lateral sclerosis (ALS) and Parkinson&#39;s disease (PD), cause the loss of hundreds of thousands of lives ...

Determining the Egg Fertilization Rate of Bemisia tabaci Using a Cytogenetic Technique

A few species of sap-sucking whiteflies are some of the most damaging terrestrial pests worldwide because of the crop damage they inflict and plant viruses they vector. Despite numerous studies of the biology of these species in different environments, a key life history parameter, offspring sex ratios, has received little attention, yet is important for predicting population dynamics. The primary sex ratio (sex ratio at oviposition) of Bemisia tabaci has never been reported but can be found by determining the egg fertilization rate of this haplodiploid insect. The technique involves the dechorionation of eggs with bleach, a series of fixation steps, and the application of the general DNA fluorescent stain, DAPI (4&#8242;,6-diamidino-2-phenylindole, a DNA-binding fluorescent dye), to bind to female and male pronuclei. Here, we present the technique, and an example of its application, to test whether an endosymbiotic bacterium, Rickettsia sp. nr. bellii, influenced the primary sex ratio of B. tabaci. This method may assist in population studies of whiteflies, or in determining if sex allocation exists with certain environmental stimuli.

Determining the Egg Fertilization Rate of Bemisia tabaci Using a Cytogenetic Technique

We present a simple cytogenetic technique using 4&#8242;,6-diamidino-2-phenylindole (DAPI) to determine the fertilization rate and primary sex ratio of the haplodiploid invasive pest Bemisia tabaci.

A few species of sap-sucking whiteflies are some of the most damaging terrestrial pests worldwide because of the crop damage they inflict and plant ...