The project was supported in part by National Institutes of Health Grants RO1 NS099409, NS075534, and CONACYT 2012-037(S) to VP.

1. Preparation
<ol>
	<li>Prepare a fly cage by making approximately 50 holes in a 100 mL capacity tri-corner plastic beaker using a hot 25 G needle (see Table of Materials).</li>
	<li>Prepare 60 mm x 15 mm Petri dishes with apple juice-agar (3% agar and 30% apple juice).</li>
	<li>Prepare fresh yeast paste by mixing dry yeast granules and water. Spread the yeast paste onto the apple agar plates to increase egg laying.</li>
	<li>Anaesthetize about 50-60 flies (use approximately equal numbers of males an...

<ol>
	<li>Pereanu, W., Spindler, S., Im, E., Buu, N., Hartenstein, V. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+emergence+of+patterned+movement+during+late+embryogenesis+of+Drosophila.">The emergence of patterned movement during late embryogenesis of Drosophila.</a> Developmental Neurobiology. 67, 1669-1685 (2007).</li><li>Suster, M. L., Bate, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Embryonic+assembly+of+a+central+pattern+generator+without+sensory+input.">Embryonic assembly of a central pattern generator without sensory input.</a> Nature. 416, 174-178 (2002).</li><li>Crisp, S., Evers, J. F., Fiala, A., Bate, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+development+of+motor+coordination+in+Drosophila+embryos.">The development of motor coordination in Drosophila embryos.</a> Development. 135, 3707-3717 (2008).</li><li>Song, W., Onishi, M., Jan, L. Y., Jan, Y. N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Peripheral+multidendritic+sensory+neurons+are+necessary+for+rhythmic+locomotion+behavior+in+Drosophila+larvae.">Peripheral multidendritic sensory neurons are necessary for rhythmic locomotion behavior in Drosophila larvae.</a> Proceedings of National Academy of Science of the United States of America. 104, 5199-5204 (2007).</li><li>Hughes, C. L., Thomas, J. B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+sensory+feedback+circuit+coordinates+muscle+activity+in+Drosophila.">A sensory feedback circuit coordinates muscle activity in Drosophila.</a> Molecular and Cellular Neuroscience. 35, 383-396 (2007).</li><li>Gorczyca, D. A., 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=Identification+of+Ppk26,+a+DEG/ENaC+channel+functioning+with+Ppk1+in+a+mutually+dependent+manner+to+guide+locomotion+behavior+in+Drosophila.">Identification of Ppk26, a DEG/ENaC channel functioning with Ppk1 in a mutually dependent manner to guide locomotion behavior in Drosophila.</a> Cell Reports. 9, 1446-1458 (2014).</li><li>Baker, R., Nakamura, N., Chandel, I., 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=Protein+O-Mannosyltransferases+affect+sensory+axon+wiring+and+dynamic+chirality+of+body+posture+in+the+Drosophila+embryo.">Protein O-Mannosyltransferases affect sensory axon wiring and dynamic chirality of body posture in the Drosophila embryo.</a> Journal of Neuroscience. 38 (7), 1850-1865 (2018).</li><li>Nakamura, N., Lyalin, D., Panin, V. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Protein+O-mannosylation+in+animal+development+and+physiology:+From+human+Disorders+to+Drosophila+phenotypes.">Protein O-mannosylation in animal development and physiology: From human Disorders to Drosophila phenotypes.</a> Seminars in Cell &amp; Developmental Biology. 21, 622-630 (2010).</li><li>Lyalin, D., 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+twisted+gene+encodes+Drosophila+protein+O-mannosyltransferase+2+and+genetically+interacts+with+the+rotated+abdomen+gene+encoding+Drosophila+protein+O-mannosyltransferase+1.">The twisted gene encodes Drosophila protein O-mannosyltransferase 2 and genetically interacts with the rotated abdomen gene encoding Drosophila protein O-mannosyltransferase 1.</a> Genetics. 172, 343-353 (2006).</li><li>Beltr&#225;n-Valero de Bernabe, D., 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=Mutations+in+the+O-Mannosyltransferase+gene+POMT1+give+rise+to+the+severe+neuronal+migration+disorder+Walker-Warburg+Syndrome.">Mutations in the O-Mannosyltransferase gene POMT1 give rise to the severe neuronal migration disorder Walker-Warburg Syndrome.</a> American Journal of Human Genetics. 71, 1033-1043 (2002).</li><li>Reeuwijk, J., 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=POMT2+mutations+cause+alpha-dystroglycan+hypoglycosylation+and+Walker-Warburg+syndrome.">POMT2 mutations cause alpha-dystroglycan hypoglycosylation and Walker-Warburg syndrome.</a> Journal of Medical Genetics. 42, 907-912 (2005).</li><li>Jaeken, J., Matthijs, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Congenital+disorders+of+glycosylation:+A+rapidly+expanding+disease+family.">Congenital disorders of glycosylation: A rapidly expanding disease family.</a> Annual Reviews of Genomics and Human Genetics. 8, 261-278 (2007).</li><li>Leyten, Q. H., Gabreels, F. J., Renier, W. O., ter Laak, H. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Congenital+muscular+dystrophy:+a+review+of+the+literature.">Congenital muscular dystrophy: a review of the literature.</a> Clinical and Neurological Neurosurgery. 98 (4), 267-280 (1996).</li><li>Roberts, D. B., Hames, B. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Drosophila:+A+Practical+Approach.+2nd+ed.">Drosophila: A Practical Approach. 2nd ed.</a> The Practical Approach Series. , 389 (1998).</li><li>Heckscher, E. S., 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=Even-Skipped++interneurons+are+core+components+of+a+sensorimotor+circuit+that+maintains+left-right+symmetric+muscle+contraction+amplitude.">Even-Skipped+ interneurons are core components of a sensorimotor circuit that maintains left-right symmetric muscle contraction amplitude.</a> Neuron. 88, 314-329 (2015).</li><li>Penjweini, 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=Long-term+monitoring+of+live+cell+proliferation+in+presence+of+PVP-Hypericin:+a+new+strategy+using+ms+pulses+of+LED+and+the+fluorescent+dye+CFSE.">Long-term monitoring of live cell proliferation in presence of PVP-Hypericin: a new strategy using ms pulses of LED and the fluorescent dye CFSE.</a> J. Microscopy. 245, 100-108 (2011).</li></ol>

Our method provides a quantitative way to analyze important embryo behaviors during development, such as peristaltic muscle contraction waves, including wave periodicity, amplitude and pattern, as well as wave effect on embryo rolling and posture. This can be useful in analyses of different mutants to study the role of specific genes in regulating these and other behaviors during embryonic development. We have used changes in muscle-specific GFP marker intensity to analyze muscle contraction amplitude, frequency and dire...

Peristaltic muscle contraction is a rhythmic motor behavior similar to walking and swimming in humans1,2,3. Embryonic muscle contractions seen in Drosophila late stage embryos represent an example of such a behavior. Drosophila is an excellent model organism to study various developmental processes because embryonic development in Drosophila is well characterized, relatively short, and easy to monitor. The overall goal of our method is to carefully record and analyze the wavelike pattern of contraction and relaxation of embryonic muscles. We used a simple, non-invasive approach that offers a detailed visualization, recording and analysis of muscle contractions. This method can also be potentially used to study other in vivo processes, such as embryonic rolling seen in late stage embryos just prior to hatching. In previous studies, embryonic muscle contractions were mostly analyzed in terms of frequency and direction1,2. In order to estimate the relative extent of contractions as they progress along the body axis in the anterior or posterior direction, we have used embryos expressing GFP specifically in muscles. This analysis provides a more quantitative way to analyze muscle contractions and to reveal how body posture in embryos is maintained during series of peristaltic waves of muscle contractions.
Peristaltic muscle contractions are controlled by central pattern generator (CPG) circuits and communications between neurons of the peripheral nervous system (PNS), the central nervous system (CNS), and muscles4,5. Failure to produce normal peristaltic muscle contractions can lead to defects such as failure to hatch2 and abnormal larval locomotion6 and can be indicative of neurological abnormalities. Live imaging of peristaltic waves of muscle contraction and detailed analysis of contraction phenotypes can help uncover pathogenic mechanisms associated with genetic defects affecting muscles and neural circuits involved in locomotion. We recently used that approach to investigate mechanisms that result in a body posture torsion phenotype of protein O-mannosyltransferase (POMT) mutants7.
Protein O-mannosylation (POM) is a special type of posttranslational modification, where a mannose sugar is added to serine or threonine residues of secretory pathway proteins8,9. Genetic defects in POM cause congenital muscular dystrophies (CMD) in humans10,11,12. We investigated the causative mechanisms of these diseases using Drosophila as a model system. We found that embryos with mutations in Drosophila protein O-mannosyltransferase genes POMT1 and POMT2 (a.k.a. rotated abdomen (rt) and twisted (tw)) show a displacement (&#34;rotation&#34;) of body segments, which results in an abnormal body posture7. Interestingly, this defect coincided with the developmental stage when peristaltic muscle contractions become prominent7.
Since abnormal body posture in POM mutant embryos arises when musculature and epidermis are already formed and peristaltic waves of coordinated muscle contractions have started, we hypothesized that abnormal body posture could be a result of abnormal muscle contractions rather than a defect in muscle or/and epidermis morphology7. CMDs can be associated with abnormal muscle contractions and posture defects13, and thus the analysis of the posture phenotype in Drosophila POMT mutants may elucidate pathological mechanisms associated with muscular dystrophies. In order to investigate the relationship between the body posture phenotype of Drosophila POMT mutants and possible abnormalities in peristaltic waves of muscle contractions, we decided to analyze muscle contractions in detail using a live imaging approach.
Our analysis of peristaltic contraction waves in Drosophila embryos revealed two distinct contraction modes, designated as type 1 and type 2 waves. Type 1 waves are simple waves propagating from anterior to posterior or vice versa. Type 2 waves are biphasic waves that initiate at the anterior end, propagate halfway in the posterior direction, momentarily halt, forming a temporal static contraction, and then, during the second phase, are swept by a peristaltic contraction that propagates forward from the posterior end. Wild-type embryos normally generate a series of contractions that consists of approximately 75% type 1 and 25% type 2 waves. In contrast, POMT mutant embryos generate type 1 and type 2 waves at approximately equal relative frequencies.
Our approach can provide detailed information for quantitative analysis of muscle contractions and embryo rolling7. This approach could also be adapted for analyses of other behaviors involving muscle contractions, such as hatching and crawling.

<table border="0" cellpadding="0" cellspacing="0" style="width:771px;" width="771">
	<colgroup>
		<col />
		<col />
		<col />
		<col />
	</colgroup>
	<tbody>
		<tr height="42">
			<td height="42" style="height:42px;width:215px;">Digital camera</td>
			<td style="width:155px;">Hamamatsu CMOS ORCA-Flash 4.0</td>
			<td style="width:119px;">C13440-20CU</td>
			<td style="width:283px;">With different emission filters</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:215px;">Forceps</td>
			<td style="width:155px;">FST Dumont</td>
			<td style="width:119px;">11254-20</td>
			<td>Tip Dimensions 0.05 mm x 0.01 mm</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:215px;">LED</td>
			<td style="width:155px;">X-cite BDX (Excelitas)</td>
			<td style="width:119px;">XLED1</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:215px;">Microscope</td>
			<td style="width:155px;">Carl Ziess Examiner D1</td>
			<td style="width:119px;">491405-0005-000</td>
			<td>Epiflourescence with time lapse</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:215px;">Needle</td>
			<td style="width:155px;">BD&#160;</td>
			<td align="right" style="width:119px;">305767</td>
			<td>25 G x 1-1/2 in</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:215px;">Paintbrush</td>
			<td style="width:155px;">Contemporary crafts</td>
			<td style="width:119px;"></td>
			<td>Any paintbrush will work</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:215px;">Petri dishes</td>
			<td style="width:155px;">VWR</td>
			<td style="width:119px;">25384-164</td>
			<td>60 mm x 15 mm</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:215px;">Software</td>
			<td style="width:155px;">HCImage Live</td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:215px;">Thread Zap Wax pen</td>
			<td style="width:155px;">Thread Zap II (by BeadSmith)(Amazon)</td>
			<td style="width:119px;">TZ1300</td>
			<td>Burner Tool</td>
		</tr>
		<tr height="23">
			<td height="23" style="height:23px;width:215px;">Tricorner plastic beaker</td>
			<td style="width:155px;">VWR</td>
			<td>25384-152</td>
			<td>100 mL</td>
		</tr>
	</tbody>
</table>

live imaging and analysis of muscle contractions in drosophila embryo

Coordinated muscle contractions are a form of rhythmic behavior seen early during development in Drosophila embryos. Neuronal sensory feedback circuits are required to control this behavior. Failure to produce the rhythmic pattern of contractions can be indicative of neurological abnormalities. We previously found that defects in protein O-mannosylation, a posttranslational protein modification, affect the axon morphology of sensory neurons and result in abnormal coordinated muscle contractions in embryos. Here, we present a relatively simple method for recording and analyzing the pattern of peristaltic muscle contractions by live imaging of late stage embryos up to the point of hatching, which we used to characterize the muscle contraction phenotype of protein O-mannosyltransferase mutants. Data obtained from these recordings can be used to analyze muscle contraction waves, including frequency, direction of propagation and relative amplitude of muscle contractions at different body segments. We have also examined body posture and taken advantage of a fluorescent marker expressed specifically in muscles to accurately determine the position of the embryo midline. A similar approach can also be utilized to study various other behaviors during development, such as embryo rolling and hatching.

Normal peristaltic muscle contractions are shown in a WT (wild-type, Canton-S) embryo in Movie 1. The average frequency of peristaltic waves of muscle contractions in our analysis was 47 contractions per hour and the average amplitude was 60% above baseline for WT embryos. Embryo rolling is shown for a WT embryo in Movie 2, with the white arrow marking the initial position of a trachea and a black arrow depicting the position of a dorsal appendage. The dorsal appendage (exterio...

Watch this Scientific Journal Video about Live Imaging and Analysis of Muscle Contractions in Drosophila Embryo at JoVE.com

Live Imaging and Analysis of Muscle Contractions in Drosophila Embryo

Here, we present a method to record embryonic muscle contractions in Drosophila embryos in a non-invasive and detail-oriented manner.

Live Imaging and Analysis of Muscle Contractions in Drosophila Embryo

Coordinated muscle contractions are a form of rhythmic behavior seen early during development in Drosophila embryos. Neuronal sensory feedback circuits ...

This method addresses how to analyze developmental processes such as muscle contractions and rolling which occur in the Drosophila embryo. Some advantages of this technique are that it is noninvasive and quite detailed, yet it is relatively simple to perform. Our method can be developed further for high-content analysis-based screening to isolate and analyze new mutations that affect embryonic muscle contractions and other developmental processes.When visualizing muscle contractions, it's important to properly time embryo collections because contractions begin only at a specific developmental stage. Step-by-step visual demonstration can greatly aid in the quantitative analysis of the developmental processes. For live imaging of mounted Drosophila embryos, place the embryos onto the stage of an epifluorescence microscope with a timelapse function and a digital camera with suitable emission filters and select a 10X water immersion objective lens.Then live video record the embryos using the appropriate microscope recording software for about one to two hours with an acquisition rate of four frames per second. At the end of the experiment, export the recorded video directly into ImageJ. Select image and crop to draw a box around each individual embryo to crop the video recordings to the size of each embryo.Click Image, Transform and Rotate to rotate the cropped images to achieve a vertical position of the embryo midline relative to the screen. To set distance measurements to micrometers, click Analyze and Set Scale, then enter the known pixel to micron ratio conversion factor for your microscope setup. All subsequent measurements will then be reported in micrometers.To analyze embryo rolling, first mark the position of one or both trachea of an embryo in the first frame of the video midway between the posterior and anterior ends and click Analyze, Tools and Region of Interest Manager. Draw an approximate seven micrometer by seven micrometer box around the trachea and click the T key on the keyboard to record this position as an XY coordinate. Mark the position of the same area of the trachea after peristaltic contractions of interest and draw a line connecting the centers of each box clicking M on the keyboard to measure the distance from the pre-contraction position to the post-contraction position.To analyze embryonic muscle contractions using embryos expressing fluorescent muscle markers, use the recording of the fluorescent readout to draw a region of interest centered around the fluorescing muscles of a particular body segment of interest. Select the Add T tab in the Region of Interest Manager to record the position of the region of interest. Click Region of Interest Manager and Measure to record the average fluorescent intensity of each region of interest selected for each frame of the video.Move the box to the centers of other body segments of interest and click Add T to record their positions to obtain regions of interest of identical size in all of the body segments to be analyzed. In the Region of Interest Manager, hold the Control key while selecting all the regions of interest recorded as XY coordinates. Click More and Multi-Measure to measure the mean fluorescent intensity of each region of interest for all of the frames of the video.This will report each measurement in a table with each region of interest as a column of the table and each frame as a row. Then transfer the table to a spreadsheet program for further analysis. Plot a graph with the frame number on the x-axis and the mean fluorescence intensity on the y-axis and convert the frame number to time using the four frames per second frame rate.The muscle contractions increase the GFP intensity as they bring more GFP into the vicinity of the focal area as more muscles get pulled in during these contractions. To determine the muscle contraction amplitude, estimate the baseline GFP intensity as the average intensity of the regions between peaks. Then assess the increase in GFP fluorescence intensity relative to this baseline.Then divide every region of interest intensity value by the baseline intensity to normalize the GFP intensity to the baseline. Compare the normalized GFP intensities at posterior, medial and anterior segments during muscle contraction wave to examine the changes in the extent of muscle contraction as the wave propagates and to determine the direction of the wave. To compare the muscle contractions on the left and right sides of the embryo, analyze the peak intensities for the same segments on both sides of the embryo.Use the contraction amplitude and the timing of the peaks to reveal the differences, if any, and the extent and the timing of the peristaltic muscle contraction waves. Here normal peristaltic muscle contractions in a wild type Drosophila embryo are shown. In this video of rolling in a wild type embryo, note that the dorsal appendage does not move while the trachea does indicating that the embryo has rolled within its shell.In this representative analysis, the muscle contraction peaks during the 165 to 178-second time period represent a single forward wave. For this embryo, no difference in the amplitude and the time of the muscle contractions was measured on the right and left sides of the embryo. A peristaltic contraction is designated as a forward type one wave if its profile has a peak that arises at the posterior region first followed by peaks at the middle and anterior regions.A backward type one wave is a peak that first arises at anterior segments and then propagates toward posterior regions. Type two waves start at one end of the embryo and proceed toward the middle regions before returning to their origin as a sweeping wave re-initiated at the opposite end. Body posture mutant embryos demonstrate an abnormal relative frequency of type one to type two wave generation that results in a body posture abnormality designated as the body torsion or rotation phenotype.To use fluorescence as a readout for the muscle contraction parameters, it is essential to use embryos with a reporter in the muscle tissue. This method can be used for the simultaneous recording of the muscle contractions of many embryos and for the assessment of the responses to various stimuli, drugs or environmental changes.

live-imaging-and-analysis-of-muscle-contractions-in-drosophila-embryo

Research

JoVE Journal

Developmental Biology

5.9K 次观看.  Texas A&M University. 此方法涉及如何分析发育过程，如肌肉收缩和滚动发生在果蝇胚胎。这种技术的一些优点是，它是非侵入性的，相当详细，但它是相对简单的执行。我们的方法可以进一步开发高含量分析为基础的筛选，以分离和分析影响胚胎肌肉收缩和其他发育过程的新突变。当可视化肌肉收缩时，正确时间胚胎收集很重要，因为收缩只在特定的发育阶段开始。分步可视化演示可以极?...