Name: multi-photon time lapse imaging to visualize development in real-time: visualization of migrating neural crest cells in zebrafish embryos
Uploaded: 2017-08-09T15:00:00.000+00:00
Duration: 10 min 13 s
Description: Watch this Scientific Journal Video about Multi-Photon Time Lapse Imaging to Visualize Development in Real-time: Visualization of Migrating Neural Crest Cells in Zebrafish Embryos at JoVE.com

作者感谢托马斯 · 席林请送礼的甘油三酯 (sox10:eGFP) 鱼和玛丽哈洛伦的慈祥礼物甘油三酯(foxd3:GFP)鱼。

The protocol described here was performed in accordance with the guidelines for the humane treatment of laboratory animals established by the University of Michigan Committee on the Use and Care of Animals (UCUCA).
1. Embryo Collection for Time-lapse Imaging
<ol>
	<li>Between 3 and 9 pm, set up male and female adult Tg(sox10:EGFP) or Tg(foxd3:GFP) transgenic zebrafish in a divided breeding tank for pairwise mating. 
	NOTE: The Tg(sox10:EGFP) and Tg(foxd3:GFP) fish, kind gifts from Thomas Schilling and Mary Halloran, respectively, were crossed into the Casper (roy -/-, nacre -/-) background to decrease auto-fluorescence and interference with pigmentation.
	<ol>
		<li>Assemble the breeding tank (slotted inner tank + solid outer tank) and fill it with reverse osmosis (RO) system water.</li>
		<li>Transfer up to 3 females and 3 males into opposing sides of the tank separated by a divider; up to 6 fish can be bred pairwise in a single breeding tank.</li>
		<li>The next morning, remove the divider shortly after the lights turn on in the vivarium. 
		NOTE: In the present study, the lights are on a 14-hour light (on at 9 am) and 10-hour dark (off at 11 pm) cycle.</li>
		<li>Allow undisturbed mating for 20 min or until sufficient numbers of embryos are produced; the embryos will be at the bottom of the breeding tank. When eggs are observed, lift the slotted inner tank out along with the fish and quickly place them (fish and inner tank) into a clean solid outer tank filled with RO water.</li>
	</ol>
	</li>
	<li>Prepare standard 1X embryo medium by adding the following per 1 L of RO water: 0.287 g (4.9 mM) NaCl, 0.127 g (0.17 mM) KCl, 0.048 g (0.33 mM) CaCl2.2H2O, 0.04 g (0.33 mM) MgSO4 (anhydrous). Stir solution until the salts are completely dissolved.
	<ol>
		<li>Add 100 &#181;L of 0.1% methylene blue as a fungicide. Add 0.25 g of sodium bicarbonate to adjust the pH to 7.75. Store medium at room temperature.</li>
	</ol>
	</li>
	<li>Collect eggs from the outer tank using an egg-collecting screen, and transfer the eggs to Petri dishes (~50 embryos per dish) containing 30 mL of 1X embryo medium. Incubate the collected eggs at 28.5 &#176;C.</li>
	<li>Embryo preparation
	<ol>
		<li>Tg(sox10:EGFP) embryos.
		<ol>
			<li>For Tg(sox10:EGFP) embryos, at 12 h post-fertilization (hpf), remove the dead eggs and assess the developmental stage of the embryos. Screen for GFP-positive embryos using a dissecting fluorescent stereomicroscope with a standard 460-490 nm band-pass excitation filter. Using forceps, remove the chorions from 3-4 embryos that express GFP, and transfer these embryos to a separate Petri dish containing 30 mL of fresh 1X embryo medium.</li>
		</ol>
		</li>
		<li>Tg(foxd3:GFP) embryos.
		<ol>
			<li>For Tg(foxd3:GFP) embryos, at 22-24 hpf, remove the dead eggs and assess the developmental stage of the embryos. Screen for positive embryos using a dissecting fluorescent stereomicroscope with a standard 460-490 nm band-pass excitation filter. Using forceps, remove the chorions from 3-4 embryos that express GFP.</li>
			<li>Prepare 1000X Phenylthiourea (PTU) stock solution by dissolving 0.75 g (3%) of PTU in 25 mL of Dimethylsulfoxide (DMSO). Aliquot and store the stock solution at 4 &#176;C. Add 30 &#181;L of 1000X PTU (3%) stock solution to 30 mL of 1X embryo medium to generate 0.003% PTU solution.</li>
			<li>Place the screened and dechorionated GFP-positive embryos in 0.003% PTU solution to inhibit pigmentation. Do not initiate treatment of the embryos with PTU prior to 20 hpf, as early treatment (at &#60;20 hpf) can have adverse effects on neural crest and neuroepithelial development.28</li>
		</ol>
		</li>
		<li>Prior to conducting the time-lapse experiment, monitor the embryos through live imaging using a standard stereomicroscope at 12-24 h intervals in age-matched comparisons as a control for temperature drift.</li>
	</ol>
	</li>
</ol>
2. Mounting of Embryo for Time-lapse Imaging
<ol>
	<li>Preparation of time-lapse embryo media
	<ol>
		<li>Prepare standard 0.4% tricaine stock solution by adding 0.004 g of tricaine to 100 mL of RO water. Aliquot (~1 mL) the stock solution into fresh 1.5-mL centrifuge tubes and store at -20 &#176;C.</li>
		<li>Prepare time-lapse embryo medium (50 mL of 1X embryo medium, 0.016% tricaine) by adding 2 mL of 0.4% tricaine solution to 48 mL of 1X embryo medium. If using embryos &#62;22 hpf, then also add 50 &#181;L of 3% PTU stock solution (final concentration.003% PTU) to the embryo medium.</li>
	</ol>
	</li>
	<li>Preparation of 2% low-melt agarose
	<ol>
		<li>Add 0.4 g of low-melt agarose powder to 20 mL of 1X embryo medium. Heat for 1-2 min or until the solution is clear and all particles are dissolved. 
		NOTE: Increasing the percentage of the agarose gel decreases the porosity of the matrix, which may physically impede the growth and development of the embryo. Therefore, the agarose solution can be lowered to 1.5% to minimize these effects. However, when the excitation beam is held stationary during laser-scanning microscopy, greater heating can occur, increasing rapidly in a logarithmic relationship with time. In this protocol, heating due to fluorophore absorption is highly localized to the focal region. Thus, in the region of interest, the temperature could increase to a value high enough (&#8805; 30 &#176;C) to melt agarose solutions made at percentages lower than 1.5, thereby directly exposing the embryo to the laser or enabling conditions in which the embryo floats out of the focal plane. For this reason, the use of agarose solutions lower than 1.5% is not recommended.</li>
		<li>Aliquot (~1 mL) the agarose solution into fresh 1.5-mL centrifuge tubes for storage. Store excess agarose solution in liquid form on a heat block (60-70 &#176;C) for 2-3 weeks.</li>
	</ol>
	</li>
	<li>Mounting the Embryo
	<ol>
		<li>To set up the open bath chamber, place a small amount of high vacuum grease on the base of the open bath chamber. Place a circular glass coverslip onto the base and screw the top of the open bath chamber onto the base until tight ( Figure 1A, B).</li>
		<li>Pipet (~500-700 &#181;L) of 2% agarose solution (60-70 &#176;C) into the open bath chamber until the base is ~3/4 filled ( Figure 1C). Note that once the agarose solution is in the open bath chamber on the lab bench, the temperature of the solution decreases approximately 1 &#176;C/s.</li>
		<li>Wait 30 s to allow the agarose to cool slightly (~30-40 &#176;C), without completely polymerizing, and subsequently transfer a single embryo to the center of the base ( Figure 1D, E).</li>
		<li>Under a fluorescent stereomicroscope, position the embryo using a 1-10 &#181;L micropipette tip, making sure that the embryo is placed near the bottom of the agarose, as the embryo may float away when covered with embryo media if it is placed too near the surface of the agarose. 
		NOTE: In the presented videos (Videos 1-3), the embryos are oriented laterally, but depending on the area of interest, the embryos can be oriented ventrally or dorsally.</li>
		<li>Monitor and reposition the embryo until the agarose has set. Once the agarose has set, use a transfer pipet to fill the assembled open chamber entirely with time-lapse embryo media ( Figure 1F).</li>
		<li>Place the open bath chamber in the quick exchange platform, which fits onto the stage adapter ( Figure 1G). Place the entire setup (embryo, open bath chamber, quick exchange platform and stage adaptor) onto the stage of the microscope immediately above the condenser ( Figure 1H).</li>
	</ol>
	</li>
</ol>
3. Microscope Set-up for Time-lapse Imaging
<ol>
	<li>Determining laser settings
	<ol>
		<li>Determining laser wavelength to use. Use a wavelength that is twice the excitation wavelength of the fluorophore of interest (e.g. wavelength between 880 and 940 nm for GFP). 
		NOTE: In the present study, the wavelength setting for GFP was between 880 and 940 nm. The higher the wavelength, the lower the output power of the laser.</li>
		<li>Determine laser transmission. A high percent of laser transmission will kill the embryo, use the lowest level of transmission (recommended). For 24 to 48 h time-lapse studies, as presented herein, keep transmission below 5%.</li>
		<li>Determine microscope detection systems and ensure that the correct filters for the fluorophore are in place. 
		NOTE: For multi-photon microscopes, there are multiple detection systems with various sensitivities for the emitted fluorescence. In general, an internal detection system has less sensitivity than an external detection system. For transgenic lines with high levels of GFP expression, the internal detection system is adequate. For transgenic lines with low levels of GFP expression or with other fluorophores (e.g., red fluorescent protein), an external detection system may be required to maintain the percent of laser transmission at a reasonable level. Regardless the detection system used, the correct filters for the fluorophore must be in place.</li>
	</ol>
	</li>
	<li>Adjusting software settings on the multi-photon microscope
	<ol>
		<li>Using the 5X objective, locate the embryo. Manually raise the stage to the highest position, and use the fine focus to position the embryo in the middle of the microscope range.</li>
		<li>Manually lower the stage, and change the 5X objective to the 25X water immersion objective (numerical aperture NA, 0.95). Carefully raise the stage to bring the embryo back into focus.</li>
		<li>In the software, click on the &#34;xyzt&#34; mode for obtaining multiple images at time intervals (t) in the x-y plane over a depth of &#34;z&#34;. Use the epifluorescence or brightfield view to find the depth of focus in the area of interest, which will demarcate the Z-stack.
		<ol>
			<li>In the software, click on &#34;begin&#34; button; for these experiments, the lateral edge of the eye was the beginning of the Z-stack. Click on &#34;end&#34; button; the midline of the embryo was the end of the Z-stack. 
			NOTE: The step size was 0.3-0.6 &#181;m and there was a total of ~200 steps for a z-stack size of 60 to 120 &#181;m).</li>
		</ol>
		</li>
		<li>Click on the menu for adjusting acquisition time and imaging frequency. For the present system, ~200 steps requires approximately 5 min for each z-stack acquisition. For adequate recovery of the fluorophore and survival of the embryo, allow for a ratio of at least 1:3 between z-stack acquisition (laser power on) and recovery time (laser power off). 
		NOTE: For example, z-stacks are acquired every 20 min with 5 min of z-stack acquisition and 15 min of recovery. For this protocol, larger z-stacks can be obtained, but would appropriately increase the time between z-stack acquisitions, resulting in fewer images over the time-lapse course.
		<ol>
			<li>With appropriate time for embryo recovery, set the time between z-stacks in the designated window. Set the total length of time for the experiment in the appropriate window.</li>
		</ol>
		</li>
		<li>Final software, laser, and embryo adjustments.
		<ol>
			<li>Turn on the live image setting to make final adjustments to the laser settings. Adjust laser transmission (see 3.1.2), gain and offset slider bars within the software to optimize the fluorescent image. Also, adjust the orientation of the embryo, as needed, depending on the length of the experiment, anticipated growth of the embryo, etc. Make sure that the area of interest remains within the frame through the duration of the experiment.</li>
			<li>Turn off the epifluorescent light source as it is no longer needed during time-lapse acquisition. Cover the stage with the laser safety box ( Figure 1I). When using the internal detection system, the laser safety box is adequate for protection against background light. Press &#34;start&#34;. 
			NOTE: However, with more sensitive external detection systems, the laser safety box does not block enough background light, and additional covers are required to prevent the disruption of image acquisition.</li>
		</ol>
		</li>
	</ol>
	</li>
</ol>
4. During Time-lapse Acquisition
<ol>
	<li>Refill the open bath chamber with time-lapse embryo media every 8-12 h (at least 2 times per day) during time-lapse acquisition through the sliding doors on the laser safety box ( Figure 1I).</li>
	<li>Before opening the doors of the laser safety box, ensure that the microscope is not actively acquiring an image. 
	NOTE: The use of heaters and circulating media systems is not necessary for time-lapse imaging experiments lasting 24 to 48 h. Indeed, the temperatures of both stage and in-line heaters are difficult to control, and during image acquisition the embryo exhibits an adequate development rate at a temperature range from 25-28 &#176;C. Moreover, circulating media systems tend to overflow and potentially damage the equipment. Thus, all embryos are routinely staged post-acquisition.</li>
</ol>
5. Post-acquisition processing
<ol>
	<li>In the software, click on the &#34;file&#34; menu and choose &#34;save&#34;.</li>
	<li>Open the file in image processing software (see the Table of Materials). Highlight the correct image series. In the software, choose the &#34;Process&#34; menu. Click on 3D Deconvolution and &#34;Apply&#34; to deconvolve each z-stack. 
	NOTE: The file is large; therefore, this step may take many hours.</li>
	<li>In the software, under the &#34;Process&#34; menu, click on &#34;maximum projection.&#34; Click on &#34;Apply&#34; to initiate maximum projection to generate 1 image per z-stack. Export each maximum projected file (1 image per z-stack) as a tiff.</li>
	<li>Import individual tiff files into video processing software. Select all tiff files and drag them into the video editor. Adjust length of each image within the video to 0.1s. Export video as mov or mp4 file.</li>
</ol>

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L., Gallina, D., Kahana, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Phenothiourea+sensitizes+zebrafish+cranial+neural+crest+and+extraocular+muscle+developmnt+to+changes+in+retinoic+acid+and+insulin-like+growth+factor+signaling.">Phenothiourea sensitizes zebrafish cranial neural crest and extraocular muscle developmnt to changes in retinoic acid and insulin-like growth factor signaling.</a> PLoS ONE. 6, e22991 (2011).</li><li>Gfrerer, L., Dougherty, M., Laio, E. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Visualization+of+craniofacial+development+in+the+sox10:kaede+transgenic+zebrafish+line+using+time-lapse+confocal+microscopy.">Visualization of craniofacial development in the sox10:kaede transgenic zebrafish line using time-lapse confocal microscopy.</a> J Vis Exp. (79), e50525 (2013).</li><li>Lopez, A. L. R., Garcai, M. D., Dickinson, M. E., Larina, I. V. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Live+confocal+microscopy+of+the+developing+mouse+embryonic+yolk+sac+vasculature.">Live confocal microscopy of the developing mouse embryonic yolk sac vasculature.</a> Methods Mol Biol. 1214, 163-172 (2015).</li><li>McGurk, P. D., Lovely, C. B., Eberhart, J. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Analyzing+craniofacial+morphogenesis+in+zebrafish+using+4D+confocal+microscopy.">Analyzing craniofacial morphogenesis in zebrafish using 4D confocal microscopy.</a> J Vis Exp. (83), e51190 (2014).</li><li>Nowotschin, S., Ferrer-Vaquer, A., Hadjantonakis, A. 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这项工作提供了通过视觉研究的核心 (P30 EY007003) 与美国国立卫生研究院 (K08EY022912-01) 国家眼科研究所的赠款资助。

多光子延时成像使体内追踪的瞬态和洄游的细胞群体。这个强大的技术可用于研究胚胎过程在真正的时间，并在本研究中，这种方法的结果加强的神经嵴细胞迁移和发展的当前知识。以前的延时成像研究通常利用共聚焦激光扫描显微镜。29,30,31,32在这里，我们目前使用的多光子技术，相比传统的共焦显微镜有着许多优点。多光子显微镜的基础是两个较长的红外波长的光子用于激发荧光。因此，有较少的散射和因而降低的背景下，启用更深层次的组织渗透，实现成像深度超过 1 毫米更有效率比共聚焦显微镜检测生物组织中。这些属性也会减小光毒性的检测，是重要的考虑因素与重复和频繁的图像采集。25,26,27从这些属性，双光子显微镜可以图像整体器官筹备和组织小动物模型中的 (如小鼠、 斑马鱼胚胎在 12 hpf-本研究是一例)。此外，这些小动物模型使基因编码荧光蛋白，可以本地化感兴趣的组织中使用。因此，多光子显微镜的使用可以大大提高图像采集的延时实验。
有很多的步骤，在此协议中，这取决于正在使用的多光子激光检测系统的类型。大多数问题本议定书与激光设置和基于使用的检测系统的图像采集。个别系统和获得技术支持的工作知识是至关重要的。此外，以往的经验，激光共聚焦扫描显微镜是用于进行故障排除。此外，初始系统设置可能会耗费时间。然而，完成系统设置后，只有小小的调整时，通常需要使用相同的转基因株系。
在本研究中，斑马鱼胚胎之间 12 和 60 hpf 用于这些实验。在这个年龄段，胚胎很小，很容易嵌入在琼脂糖，容易麻醉与 tricaine。然而，胚胎可以成为增长和不同长度的实验发展迟缓。因此，必须注意确保胚胎适当地上演在实验结束。
多光子延时成像产生细胞迁移，这不仅增强了能力，研究体内斑马鱼胚胎发育中，但是也可以应用于许多其他系统的高分辨率的、 三维的、 实时的可视化。虽然概述的议定书的重点斑马鱼神经嵴细胞迁移，这种技术很容易被改编为其他成像的目的。

先天性眼疾导致儿童失明，往往是由于异常的颅神经嵴。神经嵴细胞是瞬态的干细胞，起身从神经管形成许多机体全身。1,2,3,4,5前脑的两侧和中脑，神经嵴细胞，引起的骨和软骨的中部和额叶区和虹膜、 角膜、 小梁网和前段眼睛的巩膜。4,6,7,8神经嵴细胞从蛤蚧形式咽弓、 下巴和心脏流出道。1,3,4,9,10研究强调了贡献于眼部神经嵴和眼周发展，强调这些细胞在脊椎动物眼睛发育的重要性。事实上，中断的神经嵴细胞迁移和分化导致颅面部、 眼部异常如在阿克森费尔德丽格综合征和彼得斯加综合征。11,12,13,14,15,16,17因此，全面了解迁移、 增殖和分化的这些神经嵴细胞将提供洞察潜在先天性眼疾的复杂性。
斑马鱼是强大的模式生物研究眼发展，斑马鱼眼的结构类似于哺乳动物同行，以及许多基因进化保守斑马鱼和哺乳动物之间。18,19,20此外，斑马鱼胚胎是透明和卵生，促进眼发育的实时可视化。
扩大以前发表的作品，6，，720神经嵴细胞的迁移模式描述了使用多光子荧光延时成像上带有 SRY （性别决定区 Y） 的转录控制下的绿色荧光蛋白 (GFP) 的转基因斑马鱼线-框 10 (sox10) 或叉头框 D3 (foxd3) 基因调控区域。21,22,23,24.多光子荧光延时成像是一项强大的技术，结合先进的光学技术的激光扫描显微镜与长波长多光子荧光激发来捕获的标本，用荧光标记的高分辨率的三维图像。25,26,27多光子激光的使用已经超过标准的共焦显微镜，包括增加的组织的渗透和减少的荧光漂白明显的优势。
使用此方法，两个不同种群的神经嵴细胞迁移和洄游通道的时间变了可区分，即 foxd3 阳性神经嵴细胞在眼周间质和眼睛发育和颅面间质 sox10 阳性神经嵴细胞。使用此方法，介绍了可视化的斑马鱼的眼部和面部神经嵴迁移迁移方法，使其易于观察发展过程中实时调节的神经嵴迁移。
此协议提供信息以便在早期眼发育的甘油三酯 (sox10:EGFP) 和甘油三酯 (foxd3:GFP) 转基因斑马鱼作为示例生成定时视频。此协议可进一步用于任何来自神经嵴细胞在斑马鱼的眼部和面部结构的早期发展的高分辨率的、 三维的、 实时可视化。此外，这种方法进一步可以用于发展的其它组织和器官在斑马鱼和其他动物的模型可视化。

<table><tbody><tr><td>Breeding Tanks with Dividers</td><td>Aquaneering</td><td>ZHCT100</td><td>Crossing Tank Set (1.0-liter) Clear Polycarbonate with Lid and Insert</td></tr><tr><td>M205 FA Combi-Scope</td><td>Leica Microsystems CMS GmbH</td><td></td><td>Stereofluorescence Microscope - FusionOptics and TripleBeam</td></tr><tr><td>Sodium Chloride</td><td>Millipore (EMD)</td><td>7760-5KG</td><td>Double PE sack. CAS No. 7647-14-5, EC Number 231-598-3</td></tr><tr><td>Potassium Chloride</td><td>Millipore (EMD)</td><td>1049380500</td><td>Potassium chloride 99.999 Suprapur. CAS No. 7447-40-7, EC Number 231-211-8.</td></tr><tr><td>Calcium Chloride Dihydrate</td><td>Fisher Scientific</td><td>C79-500</td><td>Poly bottle; 500 g. CAS No. 10035-04-8</td></tr><tr><td>Magnesium Sulfate (Anhydrous)</td><td>Millipore (EMD)</td><td>MX0075-1</td><td>Poly bottle; 500 g. CAS No. 7487-88-9, EC Number 231-298-2</td></tr><tr><td>Methylene Blue</td><td>Millipore (EMD)</td><td>284-12</td><td>Glass bottle; 25 g. Powder, Certified Biological Stain</td></tr><tr><td>Sodium Bicarbonate</td><td>Millipore (EMD)</td><td>SX0320-1</td><td>Poly bottle; 500 g. Powder, GR ACS. CAS No. 144-55-8, EC Number 205-633-8</td></tr><tr><td>N-Phenylthiourea</td><td>Sigma</td><td>P7629-25G</td><td>&gt;98%. CAS Number 103-85-5, EC Number 203-151-2</td></tr><tr><td>Dimethylsulfoxide</td><td>Sigma</td><td>D8418-500ML</td><td>Molecular Biology grade. CAS Number 67-68-5, EC Number 200-664-3</td></tr><tr><td>Tricaine Methanesulfonate</td><td>Western Chemical Inc.</td><td>MS222</td><td>Tricaine-S</td></tr><tr><td>Low-Melt Agarose</td><td>ISC Bioexpress</td><td>E-3112-25</td><td>GeneMate Sieve GQA Low Melt Agarose, 25 g</td></tr><tr><td>Open Bath Chamber</td><td>Warner Instruments</td><td>RC-40HP</td><td>High Profile</td></tr><tr><td>Glass Coverslips</td><td>Fisher Scientific</td><td>12-545-102</td><td>Circle cover glass. 25 mm diameter</td></tr><tr><td>High Vacuum Grease</td><td>Fisher Scientific</td><td>14-635-5C</td><td>2.0-lb. tube. DOW CORNING CORPORATION&lt;br/&gt; 1658832</td></tr><tr><td>Quick Exchange Platform</td><td>Warner Instruments</td><td>QE-1</td><td>35 mm</td></tr><tr><td>Stage Adapter</td><td>Warner Instruments</td><td>SA-20LZ-AL</td><td>16.5 x 10 cm</td></tr><tr><td>TC SP5 MP multi-photon microscope</td><td>Leica Microsystems CMS GmbH</td><td></td><td></td></tr><tr><td>Mai Tai DeepSee Ti-Sapphire Laser</td><td>SpectraPhysics</td><td></td><td></td></tr><tr><td>Laser Safety Box</td><td>Leica Microsystems CMS GmbH</td><td></td><td></td></tr><tr><td>Leica Application Suite X (LAS X)&amp;nbsp; Software</td><td>Leica Microsystems CMS GmbH</td><td></td><td></td></tr><tr><td>Photoshop CS 6 Version 13.0 x64 Software</td><td>Adobe</td><td></td><td></td></tr><tr><td>iMovie Version 10.1.4 Software</td><td>Apple</td><td></td><td></td></tr></tbody></table>

multi-photon time lapse imaging to visualize development in real-time: visualization of migrating neural crest cells in zebrafish embryos

先天性眼和颅颌面畸形反映神经嵴，流动人口的洄游的干细胞，导致整个身体的许多细胞类型的中断。了解神经嵴的生物学已经有限，反映出缺乏可以研究体内的转基因听话模型和实时。斑马鱼是特别重要的发展模式，为研究洄游的细胞群，如神经嵴。若要检查神经嵴迁移到眼睛发育，实施的结合激光扫描显微镜与长波长多光子荧光激发的先进光学技术是拍摄高分辨率的、 三维的、 实时的转基因斑马鱼胚胎，即甘油三酯 (sox10:EGFP) 和甘油三酯 (foxd3:GFP)，在眼睛发育如sox10和foxd3已经在众多的动物模型，以调节早期神经嵴分化，他们可能代表神经嵴细胞的标记所示。多光子延时成像用来辨别的行为和早期眼发展作出贡献的两个神经嵴细胞群的迁徙模式。本议定书提供关于作为一个例子，斑马鱼神经嵴在迁移期间，生成的视频信息，并可进一步用于可视化斑马鱼和其他模式生物的很多建筑的早期发展。

多光子荧光延时成像产生一系列的视频显示斑马鱼线到眼前段中的甘油三酯 (sox10:EGFP) 和甘油三酯 (foxd3:GFP) 与颅面结构引起的颅神经嵴细胞的迁移模式。作为一个例子， sox10-12 和 30 hpf 之间的积极的神经嵴细胞迁移从神经管的边缘到颅面地区 (视频 1， 图 2)。来自前脑的两侧和中脑细胞迁移的背、 腹面的发展中国家的眼睛来填充眼周间质。此外，这些sox10阳性细胞形成鼻过程。蛤蚧神经嵴细胞迁移腹侧和引起咽拱门。延时成像的foxd3-30-60 之间的积极的神经嵴细胞 hpf 表明这些细胞迁移视杯和表面外胚层之间，通过眼裂（视频 2、图 3）。 Foxd3这些-阳性细胞围绕镜头，形成虹膜基质。
<img alt="Figure 1" class="xfigimg" src="/files/ftp_upload/56214/56214fig1.jpg"> 
图 1.安装程序。A.每个组件的安装装置，包括开放的沐浴室，快速交换平台和舞台适配器的胚胎。B.大会的开放洗澡室。C.另外 2%琼脂糖溶液 (60-70 ° C) 打开浴分庭。D.放置的胚胎在打开浴室在荧光显微镜下。E.胚胎 (24 hpf) 横向定位在聚合琼脂糖溶液在打开浴室中心。F.添加的媒体聚合的琼脂溶液的表面以完全覆盖胚胎在开放洗澡室。G.开放沐浴室放在快速交流平台，并定位在阶段适配器。H.的胚胎多光子显微镜台上安装设备的位置。一、激光安全框。推拉门 （1 和 2） 的加气开放分庭表示。<a href="//ecsource-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/56214/56214fig1large.jpg" target="_blank">请点击这里查看此图的大版本。</a>
<img alt="Figure 2" class="xfigimg" src="/files/ftp_upload/56214/56214fig2.jpg"> 
图 2.代表展开和最大投射图像从多光子延时成像对甘油三酯 (sox10:EGFP) 斑马鱼胚胎从 12 到 30 hpf。Sox10-阳性细胞迁移前脑的两侧 (P) 和中脑 (M) 来填充的眼周间质 （虚线的圈表示眼睛） 和鼻过程 （开放箭头）。从蛤蚧 (R) Sox10-阳性细胞迁移腹侧形成咽弓 （闭合箭头）。图像在时间框架中获得每 20 分钟一班，缝在一起，创建视频 1。<a href="//ecsource-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/56214/56214fig2large.jpg" target="_blank">请点击这里查看此图的大版本。</a>
<img alt="Figure 3" class="xfigimg" src="/files/ftp_upload/56214/56214fig3.jpg"> 
图 3.代表展开和最大投射图像从多光子延时成像的 Tg(foxd3:GFP) 斑马鱼胚胎从 24 到 48 hpf。Foxd3-阳性细胞进入眼的前房 （星号表示透镜） 之间的表面外胚层和视杯，与更多的细胞定位于背侧 ("D")-后 ("P") 象限相比前 ("A") 和腹侧 ("V") 象限。此外， foxd3阳性细胞迁移毗邻并通过眼裂。图像在时间框架中获得每 20 分钟一班，缝在一起，创建视频 2。<a href="//ecsource-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/56214/56214fig3large.jpg" target="_blank">请点击这里查看此图的大版本。</a>
<img alt="Figure 4" class="xfigimg" src="/files/ftp_upload/56214/56214fig4.jpg"> 
图 4.代表展开和最大投射图像从多光子延时成像的 Tg(foxd3:GFP) 从 30 至 60 岁的斑马鱼胚胎 hpf。Foxd3-阳性细胞进入眼的前房 （外的虚线的圆表示眼的外围边缘，虚线的圈表示透镜） 之间的表面外胚层和视杯，与更多的细胞定位于背侧 ("d")-后 ("p") 象限相比前 ("a") 和腹 ("v") 象限。此外， foxd3阳性细胞迁移毗邻并通过眼裂 （白色箭头表示迁移神经嵴，红色虚线划定眼裂）。在 60 hpf， foxd3-阳性细胞完全包围透镜 （闭合箭头），指示的裂缝闭合。此外，在 60 hpf， foxd3光感受器 （开放箭头），有人也表示这并不与此转录因子在神经嵴细胞中的表达。图像在时间框架中获得每 20 分钟一班，缝在一起，创建视频 3。<a href="//ecsource-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/56214/56214fig4large.jpg" target="_blank">请点击这里查看此图的大版本。</a>
<img alt="Video 1" src="/files/ftp_upload/56214/56214vid1.jpg"> 
视频 1。Tg 的延时视频 (sox10:EGFP) 斑马鱼胚胎从 12 到 30 hpf。的星号表示眼睛。<a href="//ecsource-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/56214/12h_sox10_gfp.mp4" target="_blank">请点击这里下载这个视频。</a>
<img alt="Video 2" src="/files/ftp_upload/56214/56214vid2.jpg"> 
视频 2。Tg 的延时视频 (foxd3:GFP) 斑马鱼胚胎从 24 到 48 hpf。的星号表示镜头。星号表示眼裂。d，背;v，腹;p 后, 唇瓣;a、 前。<a href="//ecsource-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/56214/24h_foxd3_gfp.mp4" target="_blank">请点击这里下载这个视频。</a>
<img alt="Video 3" src="/files/ftp_upload/56214/56214vid3.jpg"> 
视频 3。Tg 的延时视频 (foxd3:GFP) 从 30 至 60 岁的斑马鱼胚胎 hpf。星号表示镜头。箭头表示眼裂。d，背;v，腹;p 后, 唇瓣;a、 前。<a href="//ecsource-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/56214/30h_foxd3_gfp.mp4" target="_blank">请点击这里下载这个视频。</a>

Watch this Scientific Journal Video about Multi-Photon Time Lapse Imaging to Visualize Development in Real-time: Visualization of Migrating Neural Crest Cells in Zebrafish Embryos at JoVE.com

Multi-Photon Time Lapse Imaging to Visualize Development in Real-time: Visualization of Migrating Neural Crest Cells in Zebrafish Embryos

多光子时间推移成像实时可视化发展: 迁移神经嵴细胞在斑马鱼胚胎中的可视化

激光扫描与波长多光子荧光显微镜的先进光学技术组合的实施是为了捕获高分辨率的、 三维的、 实时成像中甘油三酯 (sox10:EGFP) 和甘油三酯 (foxd3:GFP) 斑马鱼胚胎神经嵴迁移。

Congenital eye and craniofacial anomalies reflect disruptions in the neural crest, a transient population of migratory stem cells that give rise to ...

multi-photon-time-lapse-imaging-to-visualize-development-real-time

Nanyang Technological University

Research

JoVE Journal

Developmental Biology

7.6K 次观看.  University of Michigan. 激光扫描与波长多光子荧光显微镜的先进光学技术组合的实施是为了捕获高分辨率的、 三维的、 实时成像中甘油三酯 (sox10:EGFP) 和甘油三酯 (foxd3:GFP) 斑马鱼胚胎神经嵴迁移。

视频: Multi-Photon Time Lapse Imaging to Visualize Development in Real-time: Visualization of Migrating Neural Crest Cells in Zebrafish Embryos

Capturing Tissue Repair in Zebrafish Larvae with Time-lapse Brightfield Stereomicroscopy

The zebrafish larval tail fin is ideal for studying tissue regeneration due to the simple architecture of the larval fin-fold, which comprises of two layers of skin that enclose undifferentiated mesenchyme, and because the larval tail fin regenerates rapidly within 2-3 days. Using this system, we demonstrate a method for capturing the repair dynamics of the amputated tail fin with time-lapse video brightfield stereomicroscopy. We demonstrate that fin amputation triggers a contraction of the amputation wound and extrusion of cells around the wound margin, leading to their subsequent clearance. Fin regeneration proceeds from proximal to distal direction after a short delay. In addition, developmental growth of the larva can be observed during all stages. The presented method provides an opportunity for observing and analyzing whole tissue-scale behaviors such as fin development and growth in a simple microscope setting, which is easily adaptable to any stereomicroscope with time-lapse capabilities.

We present a protocol for capturing the dynamics of zebrafish larval tail fin regeneration on a whole-tissue scale using brightfield-based stereomicroscopy. This technique enables capturing the regeneration dynamics with single cell resolution. This methodology can be adapted to any stereomicroscope equipped with a CCD camera and time-lapse software.

捕获组织修复的斑马鱼幼虫与时间推移明视立体显微镜

The zebrafish larval tail fin is ideal for studying tissue regeneration due to the simple architecture of the larval fin-fold, which comprises of two ...

科研

发育生物学

Time-lapse Live Imaging of Clonally Related Neural Progenitor Cells in the Developing Zebrafish Forebrain

Precise patterns of division, migration and differentiation of neural progenitor cells are crucial for proper brain development and function1,2. To understand the behavior of neural progenitor cells in the complex in vivo environment, time-lapse live imaging of neural progenitor cells in an intact brain is critically required. In this video, we exploit the unique features of zebrafish embryos to visualize the development of forebrain neural progenitor cells in vivo. We use electroporation to genetically and sparsely label individual neural progenitor cells. Briefly, DNA constructs coding for fluorescent markers were injected into the forebrain ventricle of 22 hours post fertilization (hpf) zebrafish embryos and electric pulses were delivered immediately. Six hours later, the electroporated zebrafish embryos were mounted with low melting point agarose in glass bottom culture dishes. Fluorescently labeled neural progenitor cells were then imaged for 36hours with fixed intervals under a confocal microscope using water dipping objective lens. The present method provides a way to gain insights into the in vivo development of forebrain neural progenitor cells and can be applied to other parts of the central nervous system of the zebrafish embryo.

The present video demonstrates a method which takes advantage of the combination of electroporation and confocal microscopy to perform live imaging on individual neural progenitor cells in the developing zebrafish forebrain. In vivo analysis of the development of forebrain neural progenitor cells at a clonal level can be achieved in this way.

在发展中国家斑马鱼的前脑的神经祖细胞克隆相关的定时实时成像

Precise patterns of division, migration and differentiation of neural progenitor cells are crucial for proper brain development and function1,2. To ...

神经科学

Using Light Sheet Fluorescence Microscopy to Image Zebrafish Eye Development

Light sheet fluorescence microscopy (LSFM) is gaining more and more popularity as a method to image embryonic development. The main advantages of LSFM compared to confocal systems are its low phototoxicity, gentle mounting strategies, fast acquisition with high signal to noise ratio and the possibility of imaging samples from various angles (views) for long periods of time. Imaging from multiple views unleashes the full potential of LSFM, but at the same time it can create terabyte-sized datasets. Processing such datasets is the biggest challenge of using LSFM. In this protocol we outline some solutions to this problem. Until recently, LSFM was mostly performed in laboratories that had the expertise to build and operate their own light sheet microscopes. However, in the last three years several commercial implementations of LSFM became available, which are multipurpose and easy to use for any developmental biologist. This article is primarily directed to those researchers, who are not LSFM technology developers, but want to employ LSFM as a tool to answer specific developmental biology questions. 
Here, we use imaging of zebrafish eye development as an example to introduce the reader to LSFM technology and we demonstrate applications of LSFM across multiple spatial and temporal scales. This article describes a complete experimental protocol starting with the mounting of zebrafish embryos for LSFM. We then outline the options for imaging using the commercially available light sheet microscope. Importantly, we also explain a pipeline for subsequent registration and fusion of multiview datasets using an open source solution implemented as a Fiji plugin. While this protocol focuses on imaging the developing zebrafish eye and processing data from a particular imaging setup, most of the insights and troubleshooting suggestions presented here are of general use and the protocol can be adapted to a variety of light sheet microscopy experiments.

Light sheet fluorescence microscopy is an excellent tool for imaging embryonic development. It allows recording of long time-lapse movies of live embryos in near physiological conditions. We demonstrate its application for imaging zebrafish eye development across wide spatio-temporal scales and present a pipeline for fusion and deconvolution of multiview datasets.

采用轻质板材荧光显微镜到图像斑马鱼眼睛发育

Light sheet fluorescence microscopy (LSFM) is gaining more and more popularity as a method to image embryonic development. The main advantages of LSFM ...

A Versatile Mounting Method for Long Term Imaging of Zebrafish Development

Zebrafish embryos offer an ideal experimental system to study complex morphogenetic processes due to their ease of accessibility and optical transparency. In particular, posterior body elongation is an essential process in embryonic development by which multiple tissue deformations act together to direct the formation of a large part of the body axis. In order to observe this process by long-term time-lapse imaging it is necessary to utilize a mounting technique that allows sufficient support to maintain samples in the correct orientation during transfer to the microscope and acquisition. In addition, the mounting must also provide sufficient freedom of movement for the outgrowth of the posterior body region without affecting its normal development. Finally, there must be a certain degree in versatility of the mounting method to allow imaging on diverse imaging set-ups. Here, we present a mounting technique for imaging the development of posterior body elongation in the zebrafish D. rerio. This technique involves mounting embryos such that the head and yolk sac regions are almost entirely included in agarose, while leaving out the posterior body region to elongate and develop normally. We will show how this can be adapted for upright, inverted and vertical light-sheet microscopy set-ups. While this protocol focuses on mounting embryos for imaging for the posterior body, it could easily be adapted for the live imaging of multiple aspects of zebrafish development.

Here, we present a versatile mounting method that allows for the long-term time-lapse imaging of the posterior body development of live zebrafish embryos without perturbing normal development.

斑马鱼发展长期成像的多功能安装方法

Zebrafish embryos offer an ideal experimental system to study complex morphogenetic processes due to their ease of accessibility and optical transparency. ...

Two-photon axotomy and time-lapse confocal imaging in live zebrafish embryos

Zebrafish have long been utilized to study the cellular and molecular mechanisms of development by time-lapse imaging of the living transparent embryo. Here we describe a method to mount zebrafish embryos for long-term imaging and demonstrate how to automate the capture of time-lapse images using a confocal microscope. We also describe a method to create controlled, precise damage to individual branches of peripheral sensory axons in zebrafish using the focused power of a femtosecond laser mounted on a two-photon microscope. The parameters for successful two-photon axotomy must be optimized for each microscope. We will demonstrate two-photon axotomy on both a custom built two-photon microscope and a Zeiss 510 confocal/two-photon to provide two examples.

Zebrafish trigeminal sensory neurons can be visualized in a transgenic line expressing GFP driven by a sensory neuron specific promoter 1. We have adapted this zebrafish trigeminal model to directly observe sensory axon regeneration in living zebrafish embryos. Embryos are anesthetized with tricaine and positioned within a drop of agarose as it solidifies. Immobilized embryos are sealed within an imaging chamber filled with phenylthiourea (PTU) Ringers. We have found that embryos can be continuously imaged in these chambers for 12-48 hours. A single confocal image is then captured to determine the desired site of axotomy. The region of interest is located on the two-photon microscope by imaging the sensory axons under low, non-damaging power. After zooming in on the desired site of axotomy, the power is increased and a single scan of that defined region is sufficient to sever the axon. Multiple location time-lapse imaging is then set up on a confocal microscope to directly observe axonal recovery from injury.

Here we describe a method for mounting zebrafish embryos for long-term imaging, two-photon imaging and tissue-damage techniques, and time-lapse confocal imaging.

双光子现场斑马鱼的胚胎干切断和时间推移共焦成像

Zebrafish have long been utilized to study the cellular and molecular mechanisms of development by time-lapse imaging of the living transparent embryo.  ...

生物学

A Layered Mounting Method for Extended Time-Lapse Confocal Microscopy of Whole Zebrafish Embryos

Dynamics of development can be followed by confocal time-lapse microscopy of live transgenic zebrafish embryos expressing fluorescence in specific tissues or cells. A difficulty with imaging whole embryo development is that zebrafish embryos grow substantially in length. When mounted as regularly done in 0.3-1% low melt agarose, the agarose imposes growth restriction, leading to distortions in the soft embryo body. Yet, to perform confocal time-lapse microscopy, the embryo must be immobilized. This article describes a layered mounting method for zebrafish embryos that restrict the motility of the embryos while allowing for the unrestricted growth. The mounting is performed in layers of agarose at different concentrations. To demonstrate the usability of this method, whole embryo vascular, neuronal and muscle development was imaged in transgenic fish for 55 consecutive hours. This mounting method can be used for easy, low-cost imaging of whole zebrafish embryos using inverted microscopes without requirements of molds or special equipment.

This article describes a method to mount fragile zebrafish embryos for extended time-lapse confocal microscopy. This low-cost method is easy to perform using regular glass-bottom microscopy dishes for imaging on any inverted microscope. The mounting is performed in layers of agarose at different concentrations.

全斑马鱼胚胎的延长时移共聚焦显微镜的分层安装方法

Dynamics of development can be followed by confocal time-lapse microscopy of live transgenic zebrafish embryos expressing fluorescence in specific tissues ...

Visualizing the Developing Brain in Living Zebrafish using Brainbow and Time-lapse Confocal Imaging

Development of the vertebrate nervous system requires a precise coordination of complex cellular behaviors and interactions. The use of high resolution in vivo imaging techniques can provide a clear window into these processes in the living organism. For example, dividing cells and their progeny can be followed in real time as the nervous system forms. In recent years, technical advances in multicolor techniques have expanded the types of questions that can be investigated. The multicolor Brainbow approach can be used to not only distinguish among like cells, but also to color-code multiple different clones of related cells that each derive from one progenitor cell. This allows for a multiplex lineage analysis of many different clones and their behaviors simultaneously during development. Here we describe a technique for using time-lapse confocal microscopy to visualize large numbers of multicolor Brainbow-labeled cells over real time within the developing zebrafish nervous system. This is particularly useful for following cellular interactions among like cells, which are difficult to label differentially using traditional promoter-driven colors. Our approach can be used for tracking lineage relationships among multiple different clones simultaneously. The large datasets generated using this technique provide rich information that can be compared quantitatively across genetic or pharmacological manipulations. Ultimately the results generated can help to answer systematic questions about how the nervous system develops.

In vivo imaging is a powerful tool that can be used to investigate the cellular mechanisms underlying nervous system development. Here we describe a technique for using time-lapse confocal microscopy to visualize large numbers of multicolor Brainbow-labeled cells in real time within the developing zebrafish nervous system.

使用"彩虹"和"延时共聚焦成像"可视化活斑马鱼中发育中的脑

Development of the vertebrate nervous system requires a precise coordination of complex cellular behaviors and interactions. The use of high resolution in ...

Multicolor Time-lapse Imaging of Transgenic Zebrafish: Visualizing Retinal Stem Cells Activated by Targeted Neuronal Cell Ablation

High-resolution time-lapse imaging of living zebrafish larvae can be utilized to visualize how biological processes unfold (for review see 1). Compound transgenic fish which express different fluorescent reporters in neighboring cell types provide a means of following cellular interactions 2 and/or tissue-level responses to experimental manipulations over time. In this video, we demonstrate methods that can be used for imaging multiple transgenically labeled cell types serially in individual fish over time courses that can span from minutes to several days. The techniques described are applicable to any study seeking to correlate the "behavior" of neighboring cells types over time, including: 1) serial 'catch and release' methods for imaging a large number of fish over successive days, 2) simplified approaches for separating fluorophores with overlapping excitation/emission profiles (e.g., GFP and YFP), 3) use of hypopigmented mutant lines to extend the time window available for high-resolution imaging into late larval stages of development, 4) use of membrane targeted fluorescent reporters to reveal fine morphological detail of individual cells as well as cellular details in larger populations of cells, and 5) a previously described method for chemically-induced ablation of transgenically targeted cell types; i.e., nitroreductase (NTR) mediated conversion of prodrug substrates, such as metronidazole (MTZ), to cytotoxic derivatives 3,5.
As an example of these approaches, we will visualize the ablation and regeneration of a subtype of retinal bipolar neuron within individual fish over several days. Simultaneously we will monitor several other retinal cell types, including neighboring non-targeted bipolar cells and potential degeneration-stimulated retinal stem cells (i.e., M&#971;ller glia). This strategy is being applied in our lab to characterize cell- and tissue-level (e.g., stem cell niche) responses to the selective loss and regeneration of targeted neuronal cell types.

In this video, techniques for multicolor confocal time-lapse imaging and targeted cell ablation are provided. Time-lapse imaging is used to monitor the behavior of multiple cell types of interest in vivo. Targeted cell ablation facilitates the study neural circuit function and cell-specific neuronal regeneration paradigms.

多色成像定时转基因斑马鱼：可视化由针对性的神经细胞消融激活视网膜干细胞

High-resolution time-lapse imaging of living zebrafish larvae can be utilized to visualize how biological processes unfold (for review see 1). Compound ...

Analyzing Craniofacial Morphogenesis in Zebrafish Using 4D Confocal Microscopy

Time-lapse imaging is a technique that allows for the direct observation of the process of morphogenesis, or the generation of shape. Due to their optical clarity and amenability to genetic manipulation, the zebrafish embryo has become a popular model organism with which to perform time-lapse analysis of morphogenesis in living embryos. Confocal imaging of a live zebrafish embryo requires that a tissue of interest is persistently labeled with a fluorescent marker, such as a transgene or injected dye. The process demands that the embryo is anesthetized and held in place in such a way that healthy development proceeds normally. Parameters for imaging must be set to account for three-dimensional growth and to balance the demands of resolving individual cells while getting quick snapshots of development. Our results demonstrate the ability to perform long-term in vivo imaging of fluorescence-labeled zebrafish embryos and to detect varied tissue behaviors in the cranial neural crest that cause craniofacial abnormalities. Developmental delays caused by anesthesia and mounting are minimal, and embryos are unharmed by the process. Time-lapse imaged embryos can be returned to liquid medium and subsequently imaged or fixed at later points in development. With an increasing abundance of transgenic zebrafish lines and well-characterized fate mapping and transplantation techniques, imaging any desired tissue is possible. As such, time-lapse in vivo imaging combines powerfully with zebrafish genetic methods, including analyses of mutant and microinjected embryos.

Time-lapse confocal imaging is a powerful technique useful for characterizing embryonic development. Here, we describe the methodology and characterize craniofacial morphogenesis in wild-type, as well as pdgfra, smad5, and smo mutant embryos.

使用4D共聚焦显微镜分析颅面形态的斑马鱼

Time-lapse imaging is a technique that allows for the direct observation of the process of morphogenesis, or the generation of shape. Due to their optical ...

4-Dimensional Imaging of Zebrafish Optic Cup Morphogenesis

Visual system function requires the establishment of precise tissue and organ structures. In the vertebrate eye, structural defects are a common cause of visual impairment, yet mechanisms of eye morphogenesis are still poorly understood. The basic organization of the embryonic eye is conserved throughout vertebrates, thus live imaging of zebrafish embryos has become a powerful approach to directly observe eye development at real time under normal and pathological conditions. Dynamic cell processes including movements, morphologies, interactions, division, and death can be visualized in the embryo. We have developed methods for uniform labeling of subcellular structures and timelapse confocal microscopy of early eye development in zebrafish. This protocol outlines the method of generating capped mRNA for injection into the 1-cell zebrafish embryo, mounting embryos at optic vesicle stage (~12 hours post fertilization, hpf), and performing multi-dimensional timelapse imaging of optic cup morphogenesis on a laser scanning confocal microscope, such that multiple datasets are acquired sequentially in the same imaging session. Such an approach yields data that can be used for a variety of purposes, including cell tracking, volume measurements, three-dimensional (3D) rendering, and visualization. Our approaches allow us to pinpoint the cellular and molecular mechanisms driving optic cup development, in both wild type and genetic mutant conditions. These methods can be employed directly by other groups or adapted to visualize many additional aspects of zebrafish eye development.

This protocol describes an approach for in toto labeling and multidimensional imaging of zebrafish early eye development. We describe labeling, embedding, and four dimensional (4D) imaging using laser scanning confocal microscopy, and considerations for optimizing acquisition of datasets for dissecting mechanisms of optic cup morphogenesis.

斑马鱼光学杯形态形成的四维成像

Visual system function requires the establishment of precise tissue and organ structures. In the vertebrate eye, structural defects are a common cause of ...