Name: live cell imaging to assess the dynamics of metaphase timing and cell fate following mitotic spindle perturbations
Uploaded: 2019-09-20T15:00:00
Description: Watch this Scientific Journal Video about Live Cell Imaging to Assess the Dynamics of Metaphase Timing and Cell Fate Following Mitotic Spindle Perturbations at JoVE.com

DLM is supported by an NSF GRFP. ALM is supported by funding from the Smith Family Award for Excellence in Biomedical Research.

1. Generation of hTERT-RPE-1 cells stably expressing RFP-Histone 2B (RFP-H2B) and &#945;-tubulin-EGFP (tub-EGFP)
NOTE: All steps follow aseptic techniques and take place in a biosafety level II+ (BSL2+) safety cabinet.
<ol>
	<li>Generate retrovirus carrying the genes of interest (&#945;-tubulin-EGFP and RFP-H2B) by the transfection of 293T cells with the appropriate lentiviral plasmids according to the manufacturer&#39;s instructions of the lipid-based transfection delivery system.
	<ol>
		<...

<ol>
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Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Mitosis-targeted+anti-cancer+therapies:+where+they+stand.">Mitosis-targeted anti-cancer therapies: where they stand.</a> Cell Death and Diseases. 3, 411 (2012).</li><li>Martin, M., Akhmanova, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Coming+into+Focus:+Mechanisms+of+Microtubule+Minus-End+Organization.">Coming into Focus: Mechanisms of Microtubule Minus-End Organization.</a> Trends in Cell Biology. 28, 574-588 (2018).</li><li>Maiato, H., Logarinho, E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Mitotic+spindle+multipolarity+without+centrosome+amplification.">Mitotic spindle multipolarity without centrosome amplification.</a> Nature Cell Biology. 16, 386-394 (2014).</li><li>Vitre, B. D., Cleveland, D. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Centrosomes,+chromosome+instability+(CIN)+and+aneuploidy.">Centrosomes, chromosome instability (CIN) and aneuploidy.</a> Current Opinion in Cell Biology. 24, 809-815 (2012).</li><li>Godinho, S. A., Pellman, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Causes+and+consequences+of+centrosome+abnormalities+in+cancer.">Causes and consequences of centrosome abnormalities in cancer.</a> Philosophical Transactions of the Royal Society of London. Series B, Biological Sciences. 369, (2014).</li><li>Navarro-Serer, B., Childers, E. P., Hermance, N. M., Mercadante, D., Manning, A. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Aurora+A+inhibition+limits+centrosome+clustering+and+promotes+mitotic+catastrophe+in+cells+with+supernumerary+centrosomes.">Aurora A inhibition limits centrosome clustering and promotes mitotic catastrophe in cells with supernumerary centrosomes.</a> Oncotarget. 10, 1649-1659 (2019).</li><li>Conte, N., 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=TACC1-chTOG-Aurora+A+protein+complex+in+breast+cancer.">TACC1-chTOG-Aurora A protein complex in breast cancer.</a> Oncogene. 22, 8102-8116 (2003).</li><li>Schumacher, J. M., Ashcroft, N., Donovan, P. J., Golden, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+highly+conserved+centrosomal+kinase,+AIR-1,+is+required+for+accurate+cell+cycle+progression+and+segregation+of+developmental+factors+in+Caenorhabditis+elegans+embryos.">A highly conserved centrosomal kinase, AIR-1, is required for accurate cell cycle progression and segregation of developmental factors in Caenorhabditis elegans embryos.</a> Development. 125, 4391-4402 (1998).</li><li>Asteriti, I. A., Giubettini, M., Lavia, P., Guarguaglini, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Aurora-A+inactivation+causes+mitotic+spindle+pole+fragmentation+by+unbalancing+microtubule-generated+forces.">Aurora-A inactivation causes mitotic spindle pole fragmentation by unbalancing microtubule-generated forces.</a> Molecular Cancer. 10, 131 (2011).</li><li>Chan, J. Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+clinical+overview+of+centrosome+amplification+in+human+cancers.">A clinical overview of centrosome amplification in human cancers.</a> International Journal of Biological Sciences. 7, 1122-1144 (2011).</li><li>Kramer, A., Maier, B., Bartek, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Centrosome+clustering+and+chromosomal+(in)stability:+a+matter+of+life+and+death.">Centrosome clustering and chromosomal (in)stability: a matter of life and death.</a> Molecular Oncology. 5, 324-335 (2011).</li><li>Ganem, N. J., Godinho, S. A., Pellman, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+mechanism+linking+extra+centrosomes+to+chromosomal+instability.">A mechanism linking extra centrosomes to chromosomal instability.</a> Nature. 460, 278-282 (2009).</li><li>Silkworth, W. T., Nardi, I. K., Scholl, L. M., Cimini, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Multipolar+spindle+pole+coalescence+is+a+major+source+of+kinetochore+mis-attachment+and+chromosome+mis-segregation+in+cancer+cells.">Multipolar spindle pole coalescence is a major source of kinetochore mis-attachment and chromosome mis-segregation in cancer cells.</a> PLoS One. 4, e6564 (2009).</li><li>Nigg, E. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Centrosome+aberrations:+cause+or+consequence+of+cancer+progression?.">Centrosome aberrations: cause or consequence of cancer progression?.</a> Nature reviews, Cancer. 2, 815-825 (2002).</li><li>Godinho, S. A., Kwon, M., Pellman, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Centrosomes+and+cancer:+how+cancer+cells+divide+with+too+many+centrosomes.">Centrosomes and cancer: how cancer cells divide with too many centrosomes.</a> Cancer Metastasis Reviews. 28, 85-98 (2009).</li><li>Quintyne, N. J., Reing, J. E., Hoffelder, D. R., Gollin, S. M., Saunders, W. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Spindle+multipolarity+is+prevented+by+centrosomal+clustering.">Spindle multipolarity is prevented by centrosomal clustering.</a> Science. 307, 127-129 (2005).</li><li>Magidson, V., Khodjakov, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Circumventing+photodamage+in+live-cell+microscopy.">Circumventing photodamage in live-cell microscopy.</a> Methods in Cell Biology. 114, 545-560 (2013).</li></ol>

The temporal resolution provided by the time-lapse imaging allows for the visualization and assessment of sequential cellular events within single cells. Approaches that make use of cellular synchronization followed by the collection and fixation of cells at sequential time points are limited in that comparisons are ultimately made between populations of cells. In contexts where the cellular response to perturbations may be non-uniform, or where the process being visualized is dynamic, live cell time-lapse imaging is bet...

Image-based analysis of fixed cells is commonly used to assess the cell population level changes in response to various perturbations. When combined with cell synchronization, followed by the collection and imaging of serial time points, such approaches can be used to suggest a cellular sequence of events. Nevertheless, fixed cell imaging is limited in that temporal relationships are implied for a population and not demonstrated at the level of individual cells. In this way, while fixed cell imaging and analysis is sufficient to observe robust phenotypes and steady-state changes, the ability to detect transient changes over time and changes that impact only a subpopulation of the cells is imperfect. In contrast, live cell imaging is an eloquent tool that can be used to observe cellular and subcellular processes within a single cell, or cellular population, over time and without the aid of synchronization approaches that may themselves impact cellular behavior1,2,3,4,5,6.
The formation of a bipolar mitotic spindle is essential for the proper chromosome segregation during cell division, resulting in two genetically identical daughter cells. Defects in mitotic spindle structure that corrupt mitotic progression and compromise the fidelity of chromosome segregation can result in catastrophic cell divisions and reduced cell viability. For this reason, mitotic poisons that alter spindle formation are promising therapeutics to limit the rapid proliferation of cancer cells7,8,9. Nevertheless, fixed cell analysis of spindle structure following the addition of mitotic poisons is limited in its ability to assess the dynamic process of spindle formation and may not indicate whether observed changes in spindle structure are permanent or are instead transient and may be overcome to permit successful cell division.
In this protocol, we describe an approach to assess the dynamics of mitosis following spindle perturbations by live cell imaging. Using the hTERT immortalized RPE-1 cell line engineered to express an RFP-tagged Histone 2B to visualize chromatin, together with an EGFP-tagged &#945;-tubulin to visualize microtubules, the timing of metaphase chromosome alignment, anaphase onset, and ultimately mitotic cell fate are assessed using visual cues of chromosome movement, compaction, and nuclear morphology.

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>0.05% Trypsin</td>
			<td>Gibo-Life sciences</td>
			<td>25-510</td>
			<td>A serine protease used to release adherent cells from culture dishes</td>
		</tr>
		<tr>
			<td>15ml centrifuge tubes</td>
			<td>Olympus Plastics</td>
			<td>28-101</td>
			<td></td>
		</tr>
		<tr>
			<td>20x CFI Plan Fluor objective&#160;</td>
			<td>Nikon</td>
			<td></td>
			<td>For use in Live-cell imaging to visualize both bright field and fluorescence</td>
		</tr>
		<tr>
			<td>293T Cells</td>
			<td>ATCC</td>
			<td>CRL-3216</td>
			<td>For use in retroviral transfection; used in step 1.1</td>
		</tr>
		<tr>
			<td>a-tubulin-EGFP&#160;</td>
			<td>Addgene</td>
			<td>various numbers</td>
			<td>Expression vector for alpha tubulin fused to a green fluorescent protein tag; for use in the visualization of tubulin in live-cell imaging: commercially available through addgene and other vendors</td>
		</tr>
		<tr>
			<td>Alisertib</td>
			<td>Selleckchem</td>
			<td>S1133</td>
			<td>Small molecule inhibitor of the mitotic kinase Aurora A. Stock concentration is prepared at 10mM in DMSO, and used at a final concentration of 100nM.</td>
		</tr>
		<tr>
			<td>Blasticidin</td>
			<td>Invitrogen</td>
			<td>A11139-03</td>
			<td>Antibiotic selection agent; used to select for a-tub-EGFP expressing cells</td>
		</tr>
		<tr>
			<td>C02</td>
			<td>Airgas</td>
			<td></td>
			<td>For use in cell culture and live cell imaging</td>
		</tr>
		<tr>
			<td>Chroma ET-DS Red (TRITC/Cy3)</td>
			<td>Chroma</td>
			<td>49005</td>
			<td>Single band filter set; excitation wavelength 545nm with 25nm bandwidth and emission at 605nm wavelength with 70nm bandwidth; for visualization of H2B-RFP</td>
		</tr>
		<tr>
			<td>Chroma ET-EGFP (FITC/Cy2)</td>
			<td>Chroma</td>
			<td>49002</td>
			<td>Single band filter set; excitation wavelength 470nm with 40nm bandwidth and emission at 525nm wavelength with 50nm bandwidth; for visualization of GFP-tubulin</td>
		</tr>
		<tr>
			<td>disposable glass Pastuer pipets, sterilized&#160;</td>
			<td>Fisher Scientific</td>
			<td>13-678-6A</td>
			<td>For use in aspirating cells&#160;</td>
		</tr>
		<tr>
			<td>Dulbecco&#8217;s Modified Eagle Medium (DMEM)</td>
			<td>Gibo-Life sciences</td>
			<td>11965-084</td>
			<td>Cell culture medium for growth of RPE-1 and 293T cells</td>
		</tr>
		<tr>
			<td>Fetal Bovine Serum (FBS)</td>
			<td>Gibo-Life sciences</td>
			<td>10438-026</td>
			<td>Cell culture medium supplement</td>
		</tr>
		<tr>
			<td>Lipofectamine 3000 and p3000</td>
			<td>Invitrogen</td>
			<td>L3000-015</td>
			<td>Lipid based transfection reagent for transfection of plasmids; used in 1.1.4</td>
		</tr>
		<tr>
			<td>Multi well Tissue Culture dishes</td>
			<td>Corning</td>
			<td>various</td>
			<td>for use in cell culture, transfection/infection, and live cell imaging</td>
		</tr>
		<tr>
			<td>Nikon Ti-E microscope</td>
			<td>Nikon</td>
			<td></td>
			<td>Inverted epifluorescence microscope for use in live-cell imaging</td>
		</tr>
		<tr>
			<td>NIS Elements HC&#160;</td>
			<td>Nikon</td>
			<td>Version 4.51</td>
			<td>Image acquisition and analysis software; used in sections 3 &#38; 4</td>
		</tr>
		<tr>
			<td>OPTI-MEM</td>
			<td>Gibo-Life sciences</td>
			<td>31985-070</td>
			<td>Reduced serum medium for cell transfection; used in step 1.1.3</td>
		</tr>
		<tr>
			<td>Penicillin/Streptomycin&#160;</td>
			<td>Gibo-Life sciences</td>
			<td>15140-122</td>
			<td>antibiotic used in cell culture medium</td>
		</tr>
		<tr>
			<td>phosphate bufferred saline (PBS)</td>
			<td>Caisson labs</td>
			<td>PBP06-10X1LT</td>
			<td>sterile saline solution for use with cell culture</td>
		</tr>
		<tr>
			<td>pMD2.G</td>
			<td>Addgene</td>
			<td>12259</td>
			<td>Lentiviral VSV-G envelope expression construct; used in step 1.1.4</td>
		</tr>
		<tr>
			<td>Polybrene</td>
			<td>Sigma-Aldrich</td>
			<td>H9268</td>
			<td>Cationic polymer used to enhane viral infection efficiency; used in step 1.1.10</td>
		</tr>
		<tr>
			<td>psPAX</td>
			<td>Addgene</td>
			<td>12260</td>
			<td>2nd generation lentiviral packaging plasmid; used in step 1.1.4</td>
		</tr>
		<tr>
			<td>Puromycin</td>
			<td>Invitrogen</td>
			<td>ant-pr-1</td>
			<td>Antibiotic selection agent; used to select for RFP-H2B expressing cells</td>
		</tr>
		<tr>
			<td>RFP- Histone 2B (H2B)</td>
			<td>Addgene</td>
			<td>various numbers</td>
			<td>Expression vector for red fluorescent protein-tagged histone 2B; for use in the visualization of chromatin in live-cell imaging: commercially available through Addgene and other vendors</td>
		</tr>
		<tr>
			<td>RNAi Max</td>
			<td>Invitrogen</td>
			<td>13778-150</td>
			<td>Lipid based transfection reagent for transfection of siRNA constructs</td>
		</tr>
		<tr>
			<td>RPE-1 cells</td>
			<td>ATCC</td>
			<td>CRL-4000</td>
			<td>Human retinal pigment epithelial cell line</td>
		</tr>
		<tr>
			<td>Tissue culture dish 100x20mm</td>
			<td>Corning&#160;</td>
			<td>353003</td>
			<td>for use in culturing adherent cells</td>
		</tr>
		<tr>
			<td>Zyla sCMOS camera&#160;</td>
			<td>Nikon</td>
			<td></td>
			<td>Camera attached to the micrscope, used for capturing images of cells</td>
		</tr>
	</tbody>
</table>

live cell imaging to assess the dynamics of metaphase timing and cell fate following mitotic spindle perturbations

Live cell time-lapse imaging is an important tool in cell biology that provides insight into cellular processes that might otherwise be overlooked, misunderstood, or misinterpreted by the fixed-cell analysis. While the fixed cell imaging and analysis is robust and sufficient to observe cellular steady-state, it can be limited in defining a temporal order of events at the cellular level and is ill-equipped to assess the transient nature of dynamic processes including mitotic progression. In contrast, live cell imaging is an eloquent tool that can be used to observe cellular processes at the single-cell level over time and has the capacity to capture the dynamics of processes that would otherwise be poorly represented in fixed cell imaging. Here we describe an approach to generate cells carrying fluorescently labeled markers of chromatin and microtubules and their use in live cell imaging approaches to monitor metaphase chromosome alignment and mitotic exit. We describe imaging-based techniques to assess the dynamics of spindle formation and mitotic progression, including the identification of cells at various stages in mitosis, identification&#160;and tracking of mitotic defects, and analysis of spindle dynamics and mitotic cell fate following the treatment with mitotic inhibitors.

Assessment of mitotic progression in the presence of spindle perturbations 
The regulation of spindle pole focusing is an essential step in proper bipolar spindle formation. Disruption in this process through protein depletions, drug inhibition, or alterations in centrosome number corrupt spindle structure and delay or halt mitotic progression10,11,12,<sup class="...

Watch this Scientific Journal Video about Live Cell Imaging to Assess the Dynamics of Metaphase Timing and Cell Fate Following Mitotic Spindle Perturbations at JoVE.com

Live Cell Imaging to Assess the Dynamics of Metaphase Timing and Cell Fate Following Mitotic Spindle Perturbations

Here we present a protocol to assess the dynamics of spindle formation and mitotic progression. Our application of time-lapse imaging enables the user to identify cells at various stages of mitosis, track and identify mitotic defects, and analyze spindle dynamics and mitotic cell fate upon exposure to anti-mitotic drugs.

Live cell time-lapse imaging is an important tool in cell biology that provides insight into cellular processes that might otherwise be overlooked, ...

Live cell imaging enables the observation of dynamic cellular processes over time within a single cell. These approaches are powerful for assessing the conditions that impact the dynamic process of cell division and revealing the impacts that defects in mitosis have on daughter cell proliferation and viability. Phototoxicity that results from light exposure during imaging represents a significant challenge associated with this protocol.Therefore, exposure times and the imaging interval and duration should be optimized. Using aseptic technique and a biosafety level two safety cabinet, use a sterile disposable glass Pasteur pipette to aspirate the medium from the culture plate containing the cell line carrying the expression construct of interest. Briefly wash the cells with 10 milliliters of sterile PBS with swirling and treat the cells with two milliliters of 0.05%trypsin.After two to five minutes at 37 degrees Celsius, add eight milliliters of fresh medium to the plate to stop the reaction and resuspend the detached cells with gentle pipetting. Transfer the cell solution to a sterile 15 milliliter tube and collect the cells by centrifugation. Resuspend the pellet in 10 milliliters of PBS and centrifuge the cells again.Resuspend the pellet in 10 milliliters of medium for counting and dilute the cells to a one to two times 10 to the 5th cells per milliliter of cell culture medium concentration. Then seed 500 microliters of cells into each well of a sterile 12-well imaging bottom plate and place the plate in the cell culture incubator to allow the cells to adhere to the plate's surface. No more than 30 minutes prior to imaging, add a relevant concentration of a mitotic drug to one or more of the wells and add an equal volume of the inhibitor diluent to the same number of wells as the controls.To prepare the microscope for imaging, place the plate onto the stage of an inverted epifluorescence microscope equipped with a high resolution camera, an environmental chamber preheated to 37 degrees Celsius and a delivery system for humidified 5%carbon dioxide. Select a 20 times air objective with a numerical aperture of 0.5 and equipped for the high contrast fluorescence and phase contrast, or bright field imaging and view the cells to adjust the course and find focus to bring cells into focus. To set the optimal exposure times for bright field, GFP, and RFP image acquisition, select the respective filter cubes with the appropriate excitation and emission for the fluorophores that will be imaged and click Play.If the signal is not sufficiently intense, adjust the auto exposure and in each fluorophore channel select the appropriate binning from the Format dropdown menu. Select and calibrate the microscope stage to the multi-well dish according to the manufacturer's instructions and use the image acquisition software to highlight or otherwise select the wells that will be imaged. Open the generated points control panel and under Working Area select Restricted and Border to restrict the coordinate selection area to exclude the boundaries of the well.In the Area Restriction dropdown menu, select Whole Area and select a random point placement. Set the count to six and click Randomize to select the number and distribution of the points to be captured per well, respectively. Then click on and enter the values in the time sequence control panel to select and input the time interval and the duration for collecting the images.To visualize the RFP-H2B labeled chromatin, select the images captured with the RFP filter cube in place and identify a cell entering mitosis as indicated by the initial chromatin compaction and nuclear envelope breakdown to determine the mitotic timing of the metaphase alignment and anaphase onset in individual cells. Track the cell of interest through consecutive time points in the acquired movie to determine the number of time points or minutes from mitotic entry until RFP-H2B labeled chromatin completes the alignment at the cell equator during metaphase. To monitor the mitotic timing, mitotic fidelity, and cell fate, continue to track the cell through consecutive time points to identify the time coordinate at which anaphase chromosome segregation is apparent and/or when chromatin decompaction and nuclear envelope reformation has occurred.Then visualize RFP-H2B to identify cells in each population that exhibit mitotic defects, including lagging chromosomes and chromatin bridges during anaphase chromosome segregation. By visualizing alpha tubulin-EGFP, it can be observed that cells that experience spindle disruption undergo dynamic changes as spindle pull focusing is achieved and a bipolar mitotic spindle is formed in preparation for cell division. Concurrent with spindle assembly, chromosome movement can be visualized with RFP-H2B to assess the chromosome alignment and segregation fidelity.Using live cell imaging approaches, these representative results show that cells with a normal centrosome content are able to proceed from nuclear envelope breakdown through metaphase alignment and anaphase onset to achieve a bipolar division in under 30 minutes. In the presence of extra centrosomes, nearly 50%of the cells are able to overcome a transient multipolar mitotic spindle and to form a bipolar spindle in complete cell division. The remaining cells are unable to achieve a bipolar spindle and as a result, exit mitosis through a multipolar division.Regardless of whether spindle bipolarity is achieved, cells with extra centrosomes exhibit a significantly increased duration of mitosis compared to cells with two centrosomes. Indicating that the dynamics of mitotic progression may be altered even when changes in mitotic outcome are not apparent. When defining exposure times for fluorescent channels, optimize the exposure times to limit phototoxicity.Also camera pixel binning can be selected to allow lower exposure times to be used. This procedure has applications in pharmacological screenings, invasion, and migration analysis. These approaches can also be employed to examine the efficacy of drug treatments or the dynamics of cellular motility.

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Unit 2

Cell Proliferation

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Live Cell Imaging of F-actin Dynamics via Fluorescent Speckle Microscopy (FSM)

Live Cell Imaging of F-actin Dynamics via Fluorescent Speckle Microscopy FSM

In this protocol we describe the use of Fluorescent Speckle Microscopy (FSM) to capture high-resolution images of actin dynamics in PtK1 cells. A unique ...

Assembly, Loading, and Alignment of an Analytical Ultracentrifuge Sample Cell

The analytical ultracentrifuge (AUC) is a powerful biophysical tool that allows us to record macromolecular sedimentation profiles during high speed ...

Single Cell Fate Mapping in Zebrafish

The ability to differentially label single cells has important implications in developmental biology. For instance, determining how hematopoietic, ...

Blastomere Explants to Test for Cell Fate Commitment During Embryonic Development

Fate maps, constructed from lineage tracing all of the cells of an embryo, reveal  which tissues descend from each cell of the embryo.  Although fate maps ...

Live Imaging of Apoptotic Cell Clearance during Drosophila Embryogenesis

Live Imaging of Apoptotic Cell Clearance during Drosophila Embryogenesis

The  proper elimination of unwanted or aberrant cells through apoptosis and  subsequent phagocytosis (apoptotic cell clearance) is crucial for normal  ...

Live Cell Imaging of Early Autophagy Events: Omegasomes and Beyond

Autophagy is a  cellular response triggered by the lack of nutrients, especially the absence of  amino acids. Autophagy is defined by the formation of ...

Live Cell Imaging of Primary Rat Neonatal Cardiomyocytes Following Adenoviral and Lentiviral Transduction Using Confocal Spinning Disk Microscopy

Primary rat neonatal cardiomyocytes are useful in basic in vitro cardiovascular research because they can be easily isolated in large numbers in a single ...

Identification of MyoD Interactome Using Tandem Affinity Purification Coupled to Mass Spectrometry

Skeletal muscle terminal differentiation starts with the commitment of pluripotent mesodermal precursor cells to myoblasts. These cells have still the ...

Examination of Mitotic and Meiotic Fission Yeast Nuclear Dynamics by Fluorescence Live-cell Microscopy

Live-cell imaging is a microscopy technique used to examine cell and protein dynamics in living cells. This imaging method is not toxic, generally does ...

Super-Resolution Live Cell Imaging of Subcellular Structures

There has long been a crucial tradeoff between spatial and temporal resolution in imaging. Imaging beyond the diffraction limit of light has traditionally ...