Name: ploidy manipulation of zebrafish embryos with heat shock 2 treatment
Uploaded: 2016-12-16T13:00:00
Description: Watch this Scientific Journal Video about Ploidy Manipulation of Zebrafish Embryos with Heat Shock 2 Treatment at JoVE.com

This work was supported by NIH grants R21 HD068949-01 and RO1 GM065303.

All animal experiments were conducted according to University of Wisconsin &#8211; Madison and Institutional Animal Care and Use Committee (IACUC) guidelines (University of Wisconsin &#8211; Madison Assurance number A3368-01).
1. Selecting Females for Egg Collection via Interrupted Mating
NOTE: IVF-based protocols rely on the extrusion of mature eggs from females through manual pressure 9. Previous protocols have used females directly from tanks or in pair matings without the females undergoing egg...

<ol>
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Biol. 20, 2040-2045 (2010).</li><li>Yabe, T., Ge, X., Pelegri, F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+zebrafish+maternal-effect+gene+cellular+atoll+encodes+the+centriolar+component+Sas-6+and+defects+in+its+paternal+function+promote+whole+genome+duplication.">The zebrafish maternal-effect gene cellular atoll encodes the centriolar component Sas-6 and defects in its paternal function promote whole genome duplication.</a> Dev. Biol. 312, 44-60 (2007).</li><li>Poss, K. D., Nechiporuk, A., Stringer, K. F., Lee, C., Keating, M. 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Critical steps
It is critical to work under conditions of effective in vitro fertilization. To insure a good supply of mature eggs (step 1), females set up for mating should not have been set up in mating crosses for at least 5 days and should appear gravid. During interruption of breeding, an observer can monitor 15-30 tanks adequately for the first appearance of natural egg extrusion. Interruption of mating should occur as soon as possible when the first eggs are released through natural mating...

This protocol allows the manipulation of ploidy in zebrafish embryos, such as in the generation of homozygous gynogenetic diploids from gynogenetic haploids (Figure 1) or the production of tetraploids. This is achieved by inducing a delay in cytokinesis corresponding to precisely one cell cycle (Figure 2A, 2B). The key one-cycle delay in cytokinesis is achieved by treatment with heat shock. The standard protocol of Heat Shock (HS) as originally described by Streisinger and colleagues involved a temperature pulse during the period 13-15 mpf, resulting in a one-cycle cell division stall during the first cell cycle 1. The efficiency of this protocol has been recently improved by scanning the early cell cycles with a sliding temporal window of heat shock treatment. This scan identified a later time point for a heat shock, still within the first cell cycle (22-24 mpf), that results in a higher rate of embryos with a one-cycle cell division stall, which in this case affects the second cell cycle 2. The observation that experimental manipulations during the first cell cycle interfere with cell division during the second cell cycle and cause DNA content duplication has also been reported in other fish species 3,4. We refer to this modified protocol as Heat Shock 2 (HS2 &#8211; the term &#34;2&#34; reflects that the heat pulse occurs at a later time point than the standard HS method, and that the cell cycle delay caused by HS2 occurs during the second cell cycle). These studies showed that the basis for cytokinesis arrest after heat shock is the inhibition of centriole duplication during the heat pulse, which affects spindle formation and furrow induction in the following cell cycle. HS2 results in yields of cell cycle arrest nearing 100%, and rates of ploidy duplication up to 4 times higher than standard HS 2.
Embryos treated with a heat shock during blastomere cell cycling exhibit many deleterious effects, suggesting that heat shock affects multiple processes required for cell division 2. On the other hand, if the heat shock is applied prior to the initiation of cell cycling (time period 0-30 mpf), it appears to have effects consistent with specific interference with centriole duplication and does not seem to affect other essential cell processes 2. These studies showed that the time prior to the initiation of blastomere division appears to be a developmental period amenable to using Heat Shock as a tool to specifically manipulate ploidy through centriole inhibition. The underlying cause of the apparent selectivity for heat shock on centriole duplication is unknown, but may be related to a selective degradation of centrosome substructures observed under heat stress in certain cell types, such as leukocytes 5.
Temporal synchronization of embryonic development is achieved by in vitro fertilization (IVF). Use of untreated sperm during fertilization results in diploid embryos that upon HS2-induced one-cycle cytokinesis stall become tetraploid. Use of UV-treated sperm, which carries crosslinks that inactivate its DNA, results in gynogenetic haploid embryos 6, which upon HSII-induced one-cycle cytokinesis stall become gynogenetic diploids 2. Because of the resulting whole genome duplication, the latter gynogenetic diploids are homozygous at every single locus across the genome. For conciseness, we refer to gynogenetic haploid embryos as &#34;haploids&#34;, and homozygous gynogenetic diploid embryos as &#34;homozygous diploids&#34;. If viable and fertile, homozygous diploids can be used to initiate sterile and lethal-free lines. Direct homozygosity induced by HS2 should also be readily incorporated into genetic analysis or genetic screens, since homozygous diploids from females that are heterozygous carriers of mutations exhibit rates of homozygosity at high and fixed (50%) ratios 2.
The following protocol describes steps to perform HS2 and induce ploidy duplication with full homozygosity. For tetraploid production, sperm solution should be untreated. For homozygous diploid production, sperm should be inactivated by UV treatment. In addition, as described in the Discussion, visible pigment markers can also be used to facilitate identification of homozygous diploids. Zebrafish mate primarily during the first 3 hr of the initiation of their light cycle 7, and both adults and eggs are sensitive to circadian rhythms 8, so for best results the IVF procedure should occur within this time period.

<table border="0" cellpadding="0" cellspacing="0" width="573">
	<colgroup>
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		<col />
		<col />
		<col />
	</colgroup>
	<tbody>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Zebrafish mating boxes</td>
			<td style="width:71px;">Aqua Schwarz</td>
			<td style="width:119px;">SpawningBox1</td>
			<td style="width:167px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">NaCl</td>
			<td style="width:71px;">Sigma</td>
			<td style="width:119px;">S5886</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">KCl</td>
			<td style="width:71px;">Sigma</td>
			<td style="width:119px;">P5405</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Na2HPO4</td>
			<td style="width:71px;">Sigma</td>
			<td style="width:119px;">S3264</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">KH2PO4</td>
			<td style="width:71px;">Sigma</td>
			<td style="width:119px;">P9791</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">CaCl2</td>
			<td style="width:71px;">Sigma</td>
			<td style="width:119px;">C7902</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">MgSO4-7H2O</td>
			<td style="width:71px;">Sigma</td>
			<td style="width:119px;">63138</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">NaHCO3</td>
			<td style="width:71px;">Sigma</td>
			<td style="width:119px;">S5761</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Tricaine</td>
			<td style="width:71px;">Western Chemical</td>
			<td style="width:119px;">Tricaine-D (MS 222)</td>
			<td>FDA approved (ANADA 200-226)</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Tris base</td>
			<td style="width:71px;">Sigma</td>
			<td style="width:119px;">77-86-1</td>
			<td>to prepare 1 M Tris pH 9.0</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">HCl</td>
			<td style="width:71px;">Sigma</td>
			<td style="width:119px;">920-1</td>
			<td>to prepare 1 M Tris pH 9.0</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Fish net (fine mesh) (4-5 in)</td>
			<td style="width:71px;">PennPlax</td>
			<td style="width:119px;">(ThatFishThatPlace # 212370)</td>
			<td>available in ThatFishThatPlace</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Plastic spoon</td>
			<td style="width:71px;"></td>
			<td style="width:119px;"></td>
			<td>available in most standard stores</td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;width:216px;">Dissecting scissors</td>
			<td style="width:71px;">Fine Science Tools</td>
			<td style="width:119px;">14091-09</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Dissecting forceps</td>
			<td style="width:71px;">Dumont</td>
			<td style="width:119px;">SS</td>
			<td>available from Fine Science Tools</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Dissecting stereoscope (with transmitted light source)</td>
			<td style="width:71px;">Nikon</td>
			<td style="width:119px;">SMZ645</td>
			<td>or equivalent</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Reflective light source (LED arms)</td>
			<td style="width:71px;">Fostec</td>
			<td style="width:119px;">KL1600 LED</td>
			<td>or equivalent</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Petri plates 10 cm diameter</td>
			<td style="width:71px;"></td>
			<td style="width:119px;"></td>
			<td>any maker</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Eppendorf tubes 1.5 ml</td>
			<td style="width:71px;"></td>
			<td style="width:119px;"></td>
			<td>any maker</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Ice bucket</td>
			<td style="width:71px;"></td>
			<td style="width:119px;"></td>
			<td>any maker</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Pipetteman P-1000</td>
			<td style="width:71px;"></td>
			<td style="width:119px;"></td>
			<td>any maker</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Pipette tips 1000 &#181;l</td>
			<td style="width:71px;"></td>
			<td style="width:119px;"></td>
			<td>any maker</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Narrow spatula</td>
			<td style="width:71px;">Fisher</td>
			<td style="width:119px;">14-374</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Depression glass plate</td>
			<td style="width:71px;">Corning Inc</td>
			<td style="width:119px;">722085 (Fisher cat. No 13-748B)</td>
			<td>available from Fisher Scientific</td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;width:216px;">UV lamp</td>
			<td style="width:71px;">UVP</td>
			<td style="width:119px;">Model XX-15 (cat No. UVP18006201)</td>
			<td>available from Fisher Scientific. Although not observed by us with this model, some UV sources have been observed to experience a decrease of intensity over time (if this is the case, see Modifications and Troubleshooting)</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">UV glasses</td>
			<td style="width:71px;"></td>
			<td style="width:119px;"></td>
			<td>any maker</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Paper towels</td>
			<td style="width:71px;"></td>
			<td style="width:119px;"></td>
			<td>any maker</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Kimwipes</td>
			<td style="width:71px;">Kimberly-Clark</td>
			<td style="width:119px;">06-666-11</td>
			<td>available from Fisher Scientific</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Timer stop watch</td>
			<td style="width:71px;"></td>
			<td style="width:119px;"></td>
			<td>any maker</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Wash bottle</td>
			<td style="width:71px;">Thermo Scientific</td>
			<td style="width:119px;">24020500</td>
			<td>available from Fisher Scientific</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Tea strainer</td>
			<td style="width:71px;"></td>
			<td style="width:119px;"></td>
			<td>available in kitchen stores</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">beakers, 250 ml (2)</td>
			<td style="width:71px;">Corning Inc.</td>
			<td style="width:119px;">1000250</td>
			<td>available from Fisher Scientific</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">water bath (2)</td>
			<td style="width:71px;"></td>
			<td style="width:119px;"></td>
			<td>any maker, with accurary to 0.1 C (e.g. Shel Lab H2O Bath Series)</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;"></td>
			<td style="width:71px;"></td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="44">
			<td height="44" style="height:44px;">Hanks&#8217; Solution 1</td>
			<td style="width:71px;">see above</td>
			<td style="width:119px;">see above</td>
			<td>8.0g NaCl, 0.4g KCl in 100ml ddH2O. Store at 4&#176;C.</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Hanks&#8217; Solution 2</td>
			<td style="width:71px;">see above</td>
			<td style="width:119px;">see above</td>
			<td>0.358g Anhydrous Na2HPO4, 0.6g KH2PO4 in 100ml ddH2O. Store at 4&#176;C.</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Hanks&#8217; Solution 4</td>
			<td style="width:71px;">see above</td>
			<td style="width:119px;">see above</td>
			<td>0.72g CaCl2 in 50ml ddH2O. Store at 4&#176;C.</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Hanks&#8217; Solution 5</td>
			<td style="width:71px;">see above</td>
			<td style="width:119px;">see above</td>
			<td>1.23g MgSO4 &#8729; 7H2O in 50ml ddH2O. Store at 4&#176;C.</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;"></td>
			<td style="width:71px;"></td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Hank&#39;s Premix</td>
			<td style="width:71px;">see above</td>
			<td style="width:119px;">see above</td>
			<td>add, in the following order: 10.0 ml Solution 1;&#160; 1.0 ml Solution 2;&#160; 1.0 ml Solution 4;&#160; 86.0 ml ddH2O;&#160; 1.0 ml Solution 5. Store at 4&#176;C</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;"></td>
			<td style="width:71px;"></td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Hanks&#8217; Solution 6</td>
			<td style="width:71px;">see above</td>
			<td style="width:119px;">see above</td>
			<td>0.33g NaHCO3 in 10ml ddH2O. Prepare fresh the morning of the IVF procedure.</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;"></td>
			<td style="width:71px;"></td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Hank&#39;s Solution (final solution)</td>
			<td style="width:71px;">see above</td>
			<td style="width:119px;">see above</td>
			<td>Combine 990ul of Hank&#8217;s Premix and 10ul of freshly made Solution 6 (NaHCO3 solution)</td>
		</tr>
	</tbody>
</table>

ploidy manipulation of zebrafish embryos with heat shock 2 treatment

Manipulation of ploidy allows for useful transformations, such as diploids to tetraploids, or haploids to diploids. In the zebrafish Danio rerio, specifically the generation of homozygous gynogenetic diploids is useful in genetic analysis because it allows the direct production of homozygotes from a single heterozygous mother. This article describes a modified protocol for ploidy duplication based on a heat pulse during the first cell cycle, Heat Shock 2 (HS2). Through inhibition of centriole duplication, this method results in a precise cell division stall during the second cell cycle. The precise one-cycle division stall, coupled to unaffected DNA duplication, results in whole genome duplication. Protocols associated with this method include egg and sperm collection, UV treatment of sperm, in vitro fertilization and heat pulse to cause a one-cell cycle division delay and ploidy duplication. A modified version of this protocol could be applied to induce ploidy changes in other animal species.

In spite of the one-cell cycle cytokinesis stall, DNA replication occurs normally in such embryos, resulting in the duplication of the DNA content of the embryo (Figure 1). The Streisinger Heat Shock protocol (standard HS) involves a heat pulse during the period 13-15 minutes post fertilization (mpf) and induces primarily cytokinesis arrest during the first embryonic cell division at 35 mpf 1,2, whereas the derived method described here, referred to as Heat Sho...

Watch this Scientific Journal Video about Ploidy Manipulation of Zebrafish Embryos with Heat Shock 2 Treatment at JoVE.com

Ploidy Manipulation of Zebrafish Embryos with Heat Shock 2 Treatment

A modified protocol for ploidy manipulation uses a heat shock to induce a one-cycle stall in cytokinesis in the early embryo. This protocol is demonstrated in the zebrafish but may be applicable to other species.

Manipulation of ploidy allows for useful transformations, such as diploids to tetraploids, or haploids to diploids. In the zebrafish Danio rerio, ...

Research

JoVE Journal

Developmental Biology

Mechanical Vessel Injury in Zebrafish Embryos

Zebrafish (Danio rerio) embryos have proven to be a powerful model for studying a variety of developmental and disease processes.  External development ...

Isolation and Characterization of Single Cells from Zebrafish Embryos

The zebrafish (Danio rerio) is a powerful model organism to study vertebrate development. Though many aspects of zebrafish embryonic development have been ...

Generation of Parabiotic Zebrafish Embryos by Surgical Fusion of Developing Blastulae

Surgical parabiosis of two animals of different genetic backgrounds creates a unique scenario to study cell-intrinsic versus cell-extrinsic roles for ...

Affinity Labeling Detection of Endogenous Receptors from Zebrafish Embryos

By combining the powers of Affinity Labeling and Immunoprecipitation (AFLIP), a technique for the detection of low abundance receptors in zebrafish ...

Functional Manipulation of Maternal Gene Products Using In Vitro Oocyte Maturation in Zebrafish

Functional Manipulation of Maternal Gene Products Using In Vitro Oocyte Maturation in Zebrafish

Cellular events that take place during the earliest stages of animal embryonic development are driven by maternally derived gene products deposited into ...

Biosensing Motor Neuron Membrane Potential in Live Zebrafish Embryos

The protocols described here are designed to allow researchers to study cell communication without altering the integrity of the environment in which the ...

Induction of Hypoxia in Living Frog and Zebrafish Embryos

Here, we introduce a novel system for hypoxia induction, which we developed to study the effects of hypoxia in aquatic organisms such as frog and ...

Application of RNAi and Heat-shock-induced Transcription Factor Expression to Reprogram Germ Cells to Neurons in C. elegans

Application of RNAi and Heat-shock-induced Transcription Factor Expression to Reprogram Germ Cells to Neurons in C. elegans

Studying the cell biological processes during converting the identities of specific cell types provides important insights into mechanism that maintain ...

Whole Mount Immunohistochemistry in Zebrafish Embryos and Larvae

Immunohistochemistry is a widely used technique to explore protein expression and localization during both normal developmental and disease states. ...

Imaging Intranuclear Actin Rods in Live Heat Stressed Drosophila Embryos

Imaging Intranuclear Actin Rods in Live Heat Stressed Drosophila Embryos

The purpose of this protocol is to visualize intranuclear actin rods that assemble in live Drosophila melanogaster embryos following heat stress. Actin ...