We thank Alessandro Cellerino, Tyrone Genade, Anne Brunet, Sabrina Sharp, Mickie Powell, Simone Keil, Yumi Kim, Patrick Smith, Kai Mathar and all the members of the Valenzano lab at the Max Planck Institute for Biology of Ageing for contributing to different aspects of the current killifish husbandry protocol over the years.

<ol>
	<li>Valenzano, D. R., Aboobaker, A., Seluanov, A., Gorbunova, V. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Non-canonical+aging+model+systems+and+why+we+need+them.">Non-canonical aging model systems and why we need them.</a> EMBO J. 36 (8), 959-963 (2017).</li><li>Harel, I., Brunet, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+African+Turquoise+Killifish:+A+Model+for+Exploring+Vertebrate+Aging+and+Diseases+in+the+Fast+Lane.">The African Turquoise Killifish: A Model for Exploring Vertebrate Aging and Diseases in the Fast Lane.</a> Cold Spring Harb Symp Quant Biol. 80, 275-279 (2015).</li><li>Smith, P., 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=Regulation+of+life+span+by+the+gut+microbiota+in+the+short-lived+African+turquoise+killifish.">Regulation of life span by the gut microbiota in the short-lived African turquoise killifish.</a> Elife. 6, (2017).</li><li>Cellerino, A., Valenzano, D. R., Reichard, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=From+the+bush+to+the+bench:+the+annual+Nothobranchius+fishes+as+a+new+model+system+in+biology.">From the bush to the bench: the annual Nothobranchius fishes as a new model system in biology.</a> Biol Rev Camb Philos Soc. 91 (2), 511-533 (2016).</li><li>Kim, Y., Nam, H. G., Valenzano, D. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+short-lived+African+turquoise+killifish:+an+emerging+experimental+model+for+ageing.">The short-lived African turquoise killifish: an emerging experimental model for ageing.</a> Dis Model Mech. 9 (2), 115-129 (2016).</li><li>Blazek, 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=Repeated+intraspecific+divergence+in+life+span+and+aging+of+African+annual+fishes+along+an+aridity+gradient.">Repeated intraspecific divergence in life span and aging of African annual fishes along an aridity gradient.</a> Evolution. 71 (2), 386-402 (2017).</li><li>Terzibasi, E., 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=Large+differences+in+aging+phenotype+between+strains+of+the+short-lived+annual+fish+Nothobranchius+furzeri.">Large differences in aging phenotype between strains of the short-lived annual fish Nothobranchius furzeri.</a> PLoS One. 3 (12), e3866 (2008).</li><li>Kirschner, 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=Mapping+of+quantitative+trait+loci+controlling+lifespan+in+the+short-lived+fish+Nothobranchius+furzeri--a+new+vertebrate+model+for+age+research.">Mapping of quantitative trait loci controlling lifespan in the short-lived fish Nothobranchius furzeri--a new vertebrate model for age research.</a> Aging Cell. 11 (2), 252-261 (2012).</li><li>Valenzano, D. 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=Mapping+loci+associated+with+tail+color+and+sex+determination+in+the+short-lived+fish+Nothobranchius+furzeri.">Mapping loci associated with tail color and sex determination in the short-lived fish Nothobranchius furzeri.</a> Genetics. 183 (4), 1385-1395 (2009).</li><li>Reichwald, K., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Insights+into+Sex+Chromosome+Evolution+and+Aging+from+the+Genome+of+a+Short-Lived+Fish.">Insights into Sex Chromosome Evolution and Aging from the Genome of a Short-Lived Fish.</a> Cell. 163 (6), 1527-1538 (2015).</li><li>Valenzano, D. 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=The+African+Turquoise+Killifish+Genome+Provides+Insights+into+Evolution+and+Genetic+Architecture+of+Lifespan.">The African Turquoise Killifish Genome Provides Insights into Evolution and Genetic Architecture of Lifespan.</a> Cell. 163 (6), 1539-1554 (2015).</li><li>Harel, 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=A+platform+for+rapid+exploration+of+aging+and+diseases+in+a+naturally+short-lived+vertebrate.">A platform for rapid exploration of aging and diseases in a naturally short-lived vertebrate.</a> Cell. 160 (5), 1013-1026 (2015).</li><li>Valenzano, D. R., Sharp, S., Brunet, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Transposon-Mediated+Transgenesis+in+the+Short-Lived+African+Killifish+Nothobranchius+furzeri,+a+Vertebrate+Model+for+Aging.">Transposon-Mediated Transgenesis in the Short-Lived African Killifish Nothobranchius furzeri, a Vertebrate Model for Aging.</a> G3. 1 (7), 531-538 (2011).</li><li>Harel, I., Valenzano, D. R., Brunet, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Efficient+genome+engineering+approaches+for+the+short-lived+African+turquoise+killifish.">Efficient genome engineering approaches for the short-lived African turquoise killifish.</a> Nat Protoc. 11 (10), 2010-2028 (2016).</li><li>Polacik, M., Blazek, R., Reichard, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Laboratory+breeding+of+the+short-lived+annual+killifish+Nothobranchius+furzeri.">Laboratory breeding of the short-lived annual killifish Nothobranchius furzeri.</a> Nat Protoc. 11 (8), 1396-1413 (2016).</li><li>Avdesh, 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=Regular+care+and+maintenance+of+a+zebrafish+(Danio+rerio)+laboratory:+an+introduction.">Regular care and maintenance of a zebrafish (Danio rerio) laboratory: an introduction.</a> J Vis Exp. (69), e4196 (2012).</li></ol>

All the authors declare no competing financial and non-financial interests.

We describe a protocol for laboratory culturing of turquoise killifish, including embryo collection, incubation, as well as adult fish housing, breeding, and feeding. Our protocol is specifically targeted to laboratories that conduct research focused on adult fish, in particular for experimental studies on aging and life span. Turquoise killifish can be raised on a standard zebrafish facility; however, important aspects of killifish husbandry differ from standard zebrafish care16. These adjustments include early transition from a brine-shrimp only diet to a diet supplemented with protein-rich blood worm, as well as specific steps in embryo incubation, consisting of a liquid and dry incubation stage.
Critical steps within the protocol include shipping embryos within 8 - 30 &#176;C temperature range. In case of breeding, fecundity depends on feeding frequency and food quality; therefore, we recommend at least two feedings a day per breeding tank to raise embryos yield (see section 5.6.). During embryo bleaching, do not extend embryo incubation in the bleaching solution. This may cause damage to the egg chorion and increased embryo mortality. When incubating embryos with methylene blue, do not prolong incubation of ready-to-hatch embryos for longer than 2 weeks as their viability will be dramatically reduced. For hatching turquoise killifish, low temperature of humic acid solution improves hatching and complete immersion of the embryos in the solution allows synchronized hatching. Not sufficient aeration during the incubation results in high rates of fry not able to fill the gas bladder (&#34;belly-slider&#34; phenotype, see Notes in section 5.1).
Limitation of the protocol for breeding includes the use of the sand substrate which poses challenges to centralized filtration systems and should be replaced by alternative methods in the future. Possible alternatives could be the use of zebrafish breeding tanks. Embryo bleaching could cause major physical-chemical changes in the egg chorion that could result in altered chorion physiology and hatching success. Constant exposure of embryos to methylene blue may induce long-term changes in adult fish physiology. Raising adult fish in individual tanks for survival cohort studies may negatively affect fish behavior and health. However, group housing for survival cohort studies adds significant confounding factors due to the establishment of social dominance and male territories, leading to strict social hierarchies. Therefore, we judge that isolation of male fish for survival studies is a reasonable compromise. Feeding laboratory killifish colonies with live food from un-controlled sources add a risk for external contaminations from parasites and potentially pathogenic microbial communities. In the future, an ad hoc sterile fish feed should be developed.
Future improvements to this protocol will focus on a controlled, non-live diet, which still leads to completing sexual maturation within 3 - 4 weeks. In summary, our protocol offers accessibility to turquoise killifish laboratory culturing to a wide scientific community.

Given their short life span and rapid life cycle, turquoise killifish are rapidly growing as a promising new model organism in biology1,2,3. This species is characterized by a unique life cycle for a teleost, consisting of embryonic diapause, rapid sexual maturation, and an extended post-reproductive life stage4,5. Recent work has contributed to elucidating&#160;the biology of this species both in captivity and in the wild6,7. Turquoise killifish live in seasonal fresh water bodies that form during the rainy season in the African savannah in Zimbabwe and Mozambique. During the dry season, embryos survive in the dry mud in the absence of water by&#160;virtue of a stress-resistant life stage called diapause.
Genetic maps for this species have been generated8,9, and recently their genome has been sequenced and assembled10,11. Several inbred laboratory fish strains have been developed, and transgenesis and genome editing via CRISPR/Cas9 have become available in this species, de facto promoting turquoise killifish as a competitive laboratory vertebrate model organism12,13,14.
Although a laboratory protocol has already been published for this species15, in the present protocol we develop a comprehensive list of experimental laboratory guidelines that are specifically aimed at studies that investigate aging and survival. The present protocol enables researchers already familiar with zebrafish and medaka husbandry to become versed in turquoise killifish husbandry by adopting a minimum number of key adjustments. At the same time, this protocol provides researchers without prior experience in fish husbandry&#160;with the essential tools to raise a thriving turquoise killifish colony.

<table>
	<tbody>
		<tr>
			<td>Probe calibration buffer solution pH=7.0</td>
			<td>Roth</td>
			<td>A518.1</td>
			<td>1L buffer solution pH=7.0 to calibrate water system pH-electrode</td>
		</tr>
		<tr>
			<td>Probe calibration buffer solution pH=4.0</td>
			<td>Roth</td>
			<td>P712.1</td>
			<td>1L buffer solution pH=4.0 to calibrate water system pH-electrode</td>
		</tr>
		<tr>
			<td>Conductivity standard</td>
			<td>VWR</td>
			<td>83607.260</td>
			<td>500 mL Conductivity standard 1,413 uS/cm to calibrate water system conductivity-electrode</td>
		</tr>
		<tr>
			<td>Easy Strips Test 6in1</td>
			<td>JBL</td>
			<td>2533900</td>
			<td>Test strips for determination chlorine values of system water</td>
		</tr>
		<tr>
			<td>Ammonia Test</td>
			<td>JBL</td>
			<td>2536500</td>
			<td>Test to determine ammonia content of system water</td>
		</tr>
		<tr>
			<td>Red Sea Salt</td>
			<td>Red Sea</td>
			<td></td>
			<td>22 kg bucket</td>
		</tr>
		<tr>
			<td>Sodium hydrogen carbonate</td>
			<td>VWR</td>
			<td>27780.360</td>
			<td></td>
		</tr>
		<tr>
			<td>Humic acid</td>
			<td>Sigma- Aldrich</td>
			<td>53680-50G</td>
			<td></td>
		</tr>
		<tr>
			<td>New HUFA Artemia enrichment</td>
			<td>ZM Systems UK</td>
			<td></td>
			<td>75g bottle</td>
		</tr>
		<tr>
			<td>Methylene blue</td>
			<td>Roth</td>
			<td>AE64.1</td>
			<td></td>
		</tr>
		<tr>
			<td>Hydrogen peroxide solution</td>
			<td>Sigma- Aldrich</td>
			<td>31642-1L</td>
			<td>30% (w/w)</td>
		</tr>
		<tr>
			<td>Cononut fiber</td>
			<td>Dragon</td>
			<td>ZCS010</td>
			<td></td>
		</tr>
		<tr>
			<td>Whatman paper</td>
			<td>GE healthcare</td>
			<td>3030-690</td>
			<td></td>
		</tr>
		<tr>
			<td>Ethanol pure</td>
			<td>VWR</td>
			<td>20821.467</td>
			<td>100%</td>
		</tr>
		<tr>
			<td>Silica sand</td>
			<td>local pet shop</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Artemia Eggs Premium Grade</td>
			<td>Sanders</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Bloodworm</td>
			<td>local distributor</td>
			<td></td>
			<td>Poseidon Aquakultur Germany</td>
		</tr>
		<tr>
			<td>dNTPs solution mix</td>
			<td>Biolabs</td>
			<td>N04472</td>
			<td>10mM</td>
		</tr>
		<tr>
			<td>Taq DNA polymerase</td>
			<td>Invitrogen</td>
			<td>18038-042</td>
			<td>5U/uL</td>
		</tr>
		<tr>
			<td>PCR 10x Buffer</td>
			<td>Invitrogen</td>
			<td>18038-042</td>
			<td></td>
		</tr>
		<tr>
			<td>MgCl2</td>
			<td>Invitrogen</td>
			<td>18038-042</td>
			<td>50mM</td>
		</tr>
		<tr>
			<td>NaOH</td>
			<td>Sigma- Aldrich</td>
			<td>S8045-500g</td>
			<td>50mM</td>
		</tr>
		<tr>
			<td>Tris-HCl, pH=8.0 solution</td>
			<td>Sigma- Aldrich</td>
			<td>T2694-1L</td>
			<td>1M</td>
		</tr>
		<tr>
			<td>HCl 37%</td>
			<td>Sigma- Aldrich</td>
			<td>H1758-500mL</td>
			<td></td>
		</tr>
		<tr>
			<td>Aquatic housing system</td>
			<td>Aquaneering</td>
			<td></td>
			<td>Central filtration equipped aquatic system</td>
		</tr>
		<tr>
			<td>Fish tanks</td>
			<td>Aquaneering</td>
			<td></td>
			<td>volume: 0.8L, 2.8L, 9.5L; equipped with baffles, fry mesh and lids</td>
		</tr>
		<tr>
			<td>Orbital shaker</td>
			<td>VWR</td>
			<td>89032-100</td>
			<td>model 5000</td>
		</tr>
		<tr>
			<td>Microbiological incubator</td>
			<td>Thermo Scientific, Heratherm</td>
			<td>50125882</td>
			<td>model IMC18; for storage embryos in the liquid phase, set to t=27-28&#176;C</td>
		</tr>
		<tr>
			<td>Cooling Incubator</td>
			<td>Binder</td>
			<td>9020-0209</td>
			<td>model KT115; for storage embryos in the solid phase, set to t=27-28&#176;C</td>
		</tr>
		<tr>
			<td>Hatching incubator</td>
			<td>Thermo Scientific, Heratherm</td>
			<td>51028114</td>
			<td>model OGS180; for embryos hatching, set to t=27-28&#176;C</td>
		</tr>
		<tr>
			<td>Stereomicroscope</td>
			<td>Leica</td>
			<td></td>
			<td>model M80</td>
		</tr>
		<tr>
			<td>Breeding sand/hatching boxes</td>
			<td>Roth</td>
			<td>1598.1</td>
			<td>1000mL</td>
		</tr>
		<tr>
			<td>Petri dish</td>
			<td>Sarstedt</td>
			<td>82.1473</td>
			<td>92x16mm</td>
		</tr>
		<tr>
			<td>50mL Conical tube</td>
			<td>Sarstedt</td>
			<td>62.547.254</td>
			<td></td>
		</tr>
		<tr>
			<td>15mL Conical tube</td>
			<td>Sarstedt</td>
			<td>62.554.002</td>
			<td></td>
		</tr>
		<tr>
			<td>Disposable Plastic Pasteur pipette</td>
			<td>Roth</td>
			<td>EA71.1</td>
			<td>2mL; For fish feeding with bloodworms, or embryos selection cut off the tip to open 3-4mm diameter</td>
		</tr>
		<tr>
			<td>Serological pipette</td>
			<td>Sarstedt</td>
			<td>86.1689.001</td>
			<td>50mL</td>
		</tr>
		<tr>
			<td>Syringe</td>
			<td>Henke Sass Wolf</td>
			<td>4100-000V0</td>
			<td>10mL</td>
		</tr>
		<tr>
			<td>Metal strainer</td>
			<td></td>
			<td></td>
			<td>fineness &#60;1mm; for embryos collection</td>
		</tr>
		<tr>
			<td>Tweezers</td>
			<td>Dumont</td>
			<td>0508-5/45-PO</td>
			<td>type5/45; for embryos transfer</td>
		</tr>
		<tr>
			<td>25L Brine shrimps hatcher</td>
			<td>Aquaneering</td>
			<td>ZHBS25</td>
			<td>main hatcher</td>
		</tr>
		<tr>
			<td>500mL Brine shrimps hatcher</td>
			<td>JBL</td>
			<td>6106100</td>
			<td>model Artemio 1; backuo hatcher</td>
		</tr>
		<tr>
			<td>Narrow-mesh fish nets</td>
			<td>JBL</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Sand beaker</td>
			<td>VWR</td>
			<td>BURK7102-5000</td>
			<td>5000mL</td>
		</tr>
		<tr>
			<td>Brine shrimps separation beaker</td>
			<td>VWR</td>
			<td>BURK7102-2000</td>
			<td>2000mL</td>
		</tr>
		<tr>
			<td>Plastic zipper bag</td>
			<td>Roth</td>
			<td>P279.2</td>
			<td>for dead fish storage</td>
		</tr>
		<tr>
			<td>Pipetboy</td>
			<td>Integra</td>
			<td>155000</td>
			<td>model Pipetboy acu2</td>
		</tr>
		<tr>
			<td>Parafilm</td>
			<td>P-Lab</td>
			<td>P701605</td>
			<td></td>
		</tr>
		<tr>
			<td>Air tubing</td>
			<td>www.zajac.de</td>
			<td>AQ380</td>
			<td>4-6 mm diameter</td>
		</tr>
		<tr>
			<td>1L Glass bottle</td>
			<td>VWR</td>
			<td>215-1595</td>
			<td></td>
		</tr>
		<tr>
			<td>2L Glass bottle</td>
			<td>VWR</td>
			<td>215-1596</td>
			<td></td>
		</tr>
		<tr>
			<td>500mL Squeeze bottle</td>
			<td>Roth</td>
			<td>K665.1</td>
			<td>for fish feeding with brine shrimps</td>
		</tr>
		<tr>
			<td>120 micron brine shrimps strainer</td>
			<td>Florida Aqua Farms</td>
			<td>BB-PC2</td>
			<td>for brine shrimps/bloodworm collection</td>
		</tr>
		<tr>
			<td>Finish filter socks</td>
			<td>Aquaneering</td>
			<td>MFVB025C</td>
			<td>25 micron</td>
		</tr>
		<tr>
			<td>Central filtration fish housing system</td>
			<td></td>
			<td></td>
			<td>Aquaneering, Techniplast, Aquatic Habitats, Aqua Schwarz</td>
		</tr>
	</tbody>
</table>

a protocol for laboratory housing of turquoise killifish (nothobranchius furzeri)

The development of husbandry practices in non-model laboratory fish used for experimental purposes has greatly benefited from the establishment of reference fish model systems, such as zebrafish and medaka. In recent years, an emerging fish &#8211; the turquoise killifish (Nothobranchius furzeri) &#8211; has been adopted by a growing number of research groups in the fields of biology of aging and ecology. With a captive life span of 4 - 8 months, this species is the shortest-lived vertebrate raised in captivity and allows the scientific community to test &#8211; in a short time &#8211; experimental interventions that can lead to alterations of the aging rate and life expectancy. Given the unique biology of this species, characterized by embryonic diapause, explosive sexual maturation, marked morphological and behavioral sexual dimorphism - and their relatively short adult life span -&#160;ad hoc husbandry practices are in urgent demand. This protocol reports a set of key husbandry measures that allow optimal turquoise killifish laboratory care, enabling the scientific community to adopt this species as a powerful laboratory animal model.

Turquoise killifish proper husbandry results in median survival ranging between 12 - 18 weeks in the GRZ strain (e.g. Figure 4A). Variations of median survival depend on diet, feeding frequency, and housing temperature conditions. Poor husbandry results in survival curves presenting increased early mortality and repetitive, sudden drops of survival throughout time, characterized by several inflection points (Figure 4B).
<img alt="Figure 1" class="xfigimg" src="/files/ftp_upload/57073/57073fig1.jpg" /> 
Figure 1: Representative embryonic developmental stages with respective incubation substrate. (A) Freshly collected embryos, incubated in methylene blue solution in the incubator at 28 &#176;C. (B) Embryos ready to be transferred to solid medium, either filter paper or coconut fiber. (C) Embryos ready to be hatched, displaying typical golden irises. The scale bar is equal to 1 mm. <a href="https://cloudflare-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/57073/57073fig1large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
<img alt="Figure 2" class="xfigimg" src="/files/ftp_upload/57073/57073fig2.jpg" /> 
Figure 2: Stages of turquoise killifish post-hatching development. <a href="https://cloudflare-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/57073/57073fig2large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
<img alt="Figure 3" class="xfigimg" src="/files/ftp_upload/57073/57073fig3.jpg" /> 
Figure 3: Representative fish ID tag for fish from stage 3 onwards. <a href="https://cloudflare-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/57073/57073fig3large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
<img alt="Figure 4" class="xfigimg" src="/files/ftp_upload/57073/57073fig4.jpg" /> 
Figure 4: Representative survival curve for 70 male turquoise killifish. (A) Typical survival curve for laboratory-raised turquoise killifish. (B) Comparison of survival curves obtained from fish raised under optimal husbandry conditions (black) and poor husbandry (red and blue). The dashed red horizontal line indicates 50% survival, intersecting survival curve at median life span (indicated on the x-axis). <a href="https://cloudflare-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/57073/57073fig4large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>ID</td>
			<td colspan="2">Forward primer</td>
			<td colspan="2">Reverse primer</td>
			<td>Size range (bp)</td>
		</tr>
		<tr>
			<td>*NfuSU0007</td>
			<td colspan="2">GGCTAAGCCTTGCTGACAGA</td>
			<td colspan="2">CAGGGAGCTGAAAACCTCAG</td>
			<td>166 - 214</td>
		</tr>
		<tr>
			<td>*NfuSU0010</td>
			<td colspan="2">CGCAGTCTGATCAAATCGTGT</td>
			<td colspan="2">TGTTTGAAGGTTCACATTCATTATC</td>
			<td>220 - 272</td>
		</tr>
		<tr>
			<td>NfuSU0016</td>
			<td colspan="2">CATGGCTAAACCGTGATGAA</td>
			<td colspan="2">GAAGGACGCCAGCTATGAAG</td>
			<td>209 - 240</td>
		</tr>
		<tr>
			<td>NfuSU0022</td>
			<td colspan="2">AACACAGCTCTCGTAAGGAGGTA</td>
			<td colspan="2">TTCAGACTTGTCTTACTACCATGTTT</td>
			<td>198 - 238</td>
		</tr>
		<tr>
			<td>NfuSU0027</td>
			<td colspan="2">TCCAGCTGAATCGGTAATGA</td>
			<td colspan="2">AAACTCGAGGGTGCAATCTG</td>
			<td>164 - 226</td>
		</tr>
		<tr>
			<td>NfuSU0049</td>
			<td colspan="2">CTGGACAAAGTGCCAATCAC</td>
			<td colspan="2">CTCCCACAGTCCCAAAACAT</td>
			<td>196 - 197</td>
		</tr>
		<tr>
			<td>NfuSU0050</td>
			<td colspan="2">CCAGAATGAACAATACTCAGATCAA</td>
			<td colspan="2">GCAGCTTAGTTTAATGATATCACAATG</td>
			<td>252 - 295</td>
		</tr>
		<tr>
			<td>NfuSU0060</td>
			<td colspan="2">CTAGCCACTCCCCTGGTTTA</td>
			<td colspan="2">CCGTCACGATGTGCTGATAC</td>
			<td>216 - 248</td>
		</tr>
		<tr>
			<td>NfuFLI0030</td>
			<td colspan="2">CAGAAGCTAAAGGCCAGACG</td>
			<td colspan="2">GGGAAACAATAGGGAACCAC</td>
			<td>174 - 205</td>
		</tr>
		<tr>
			<td>*NfuFLI0091</td>
			<td colspan="2">ACGCTGACTCTACCCAGTC</td>
			<td colspan="2">CTGCCTGCTACTGACAATG</td>
			<td>355 - 373</td>
		</tr>
		<tr>
			<td colspan="6">*- sex determination markers</td>
		</tr>
	</tbody>
</table>
Table 1: Genotyping primers for strain identification.

Watch this Scientific Journal Video about A Protocol for Laboratory Housing of Turquoise Killifish Nothobranchius furzeri at JoVE.com

A Protocol for Laboratory Housing of Turquoise Killifish Nothobranchius furzeri

Laboratory housing of turquoise killifish can be scaled up&#160;to house and efficiently raise thousands of individual fish in a centralized water filtration system, employing the same infrastructure used for standard zebrafish facilities. Here we detail a list of standardized procedures that allow efficient killifish maintenance.

A Protocol for Laboratory Housing of Turquoise Killifish (Nothobranchius furzeri)

The development of husbandry practices in non-model laboratory fish used for experimental purposes has greatly benefited from the establishment of ...

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16.7K Views.  Max Planck Institute for the Biology of Ageing. Laboratory housing of turquoise killifish can be scaled up to house and efficiently raise thousands of individual fish in a centralized water filtration system, employing the same infrastructure used for standard zebrafish facilities. Here we detail a list of standardized procedures that allow efficient killifish maintenance.

Video: A Protocol for Laboratory Housing of Turquoise Killifish Nothobranchius furzeri

Protocol for Mosquito Rearing (A. gambiae)

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Protocol for Mosquito Rearing A. gambiae

This video illustrates the general techniques used to rear Anopheles gambiae in the laboratory. The methods for caring for laboratory mosquitoes are demonstrated through all stages of the organism's life cycle from larvae to pupae to blood-feeding adults.

This protocol describes mosquito rearing in the insectary. The insectary rooms are maintained at 28&deg;C and ~80% humidity, with a 12 hr. day/night ...

Neutrophil Isolation Protocol

Neutrophil polymorphonuclear granulocytes (PMN) are the most abundant leukocytes in humans and among the first cells to arrive on the site of inflammatory immune response. Due to their key role in inflammation, neutrophil functions such as locomotion, cytokine production, phagocytosis, and tumor cell combat are extensively studied. To characterize the specific functions of neutrophils, a clean, fast, and reliable method of separating them from other blood cells is desirable for in vitro studies, especially since neutrophils are short-lived and should be used within 2-4 hours of collection. Here, we demonstrate a standard density gradient separation method to isolate human neutrophils from whole blood using commercially available separation media that is a mixture of sodium metrizoate and Dextran 500. The procedure consists of layering whole blood over the density gradient medium, centrifugation, separation of neutrophil layer, and lysis of residual erythrocytes. Cells are then washed, counted, and resuspended in buffer to desired concentration. When performed correctly, this method has been shown to yield samples of >95% neutrophils with >95% viability.

Neutrophils are among the first cells to arrive on the site of inflammatory immune response, and their functions and mechanisms have been studied extensively in vitro. We demonstrate a standard density gradient separation method to isolate human neutrophils from whole blood using commercially available separation media.

Neutrophil polymorphonuclear granulocytes (PMN) are the most abundant leukocytes in humans and among the first cells to arrive on the site of inflammatory ...

Protocol for Culturing Sympathetic Neurons from Rat Superior Cervical Ganglia (SCG)

The superior cervical ganglia (SCG) in rats are small, glossy, almond-shaped structures that contain sympathetic neurons.  These neurons provide sympathetic innervations for the head and neck regions and they constitute a well-characterized and relatively homogeneous population (4).  Sympathetic neurons are dependent on nerve growth factor (NGF) for survival, differentiation and axonal growth and the wide-spread availability of NGF facilitates their culture and experimental manipulation (2, 3, 6).  For these reasons, cultured sympathetic neurons have been used in a wide variety of studies including neuronal development and differentiation, mechanisms of programmed and pathological cell death, and signal transduction (1, 2, 5, and 6).  Dissecting out the SCG from newborn rats and culturing sympathetic neurons is not very complicated and can be mastered fairly quickly.  In this article, we will describe in detail how to dissect out the SCG from newborn rat pups and to use them to establish cultures of sympathetic neurons.  The article will also describe the preparatory steps and the various reagents and equipment that are needed to achieve this.

Protocol for Culturing Sympathetic Neurons from Rat Superior Cervical Ganglia SCG

This is a protocol describing how to isolate and culture primary sympathetic neurons from superior cervical ganglia (SCG) of newborn rat pups.

The superior cervical ganglia (SCG) in rats are small, glossy, almond-shaped structures that contain sympathetic neurons.  These neurons provide ...

A Protocol for the Production of KLRG1 Tetramer

Killer cell lectin-like receptor G1 (KLRG1) is a type II transmembrane glycoprotein inhibitory receptor belonging to the C type lectin-like superfamily. KLRG1 exists both as a monomer and as a disulfide-linked homodimer. This well-conserved receptor is found on the most mature and recently activated NK cells as well as on a subset of effector/memory T cells.
Using KLRG1 tetramer as well as other methods, E-, N-, and R-cadherins were identified as KLRG1 ligands. These Ca2+-dependent cell-cell adhesion molecules comprises of an extracellular domain containing five cadherin repeats responsible for cell-cell interactions, a transmembrane domain and a cytoplasmic domain that is linked to the actin cytoskeleton. 
Generation of the KLRG1 tetramer was essential to the identification of the KLRG1 ligands. KLRG1 tetramer is also a unique tool to elucidate the roles cadherin and KLRG1 play in regulating the immune response and tissue integrity.

This protocol describes the production of KLRG1 tetramer, which is a powerful tool for the analysis of KLRG1 ligands.

Killer cell lectin-like receptor G1 (KLRG1) is a type II transmembrane glycoprotein inhibitory receptor belonging to the C type lectin-like superfamily. ...

A Protocol for Computer-Based Protein Structure and Function Prediction

Genome sequencing projects have ciphered millions of protein sequence, which require knowledge of their structure and function to improve the understanding of their biological role. Although experimental methods can provide detailed information for a small fraction of these proteins, computational modeling is needed for the majority of protein molecules which are experimentally uncharacterized. The I-TASSER server is an on-line workbench for high-resolution modeling of protein structure and function. Given a protein sequence, a typical output from the I-TASSER server includes secondary structure prediction, predicted solvent accessibility of each residue, homologous template proteins detected by threading and structure alignments, up to five full-length tertiary structural models, and structure-based functional annotations for enzyme classification, Gene Ontology terms and protein-ligand binding sites. All the predictions are tagged with a confidence score which tells how accurate the predictions are without knowing the experimental data. To facilitate the special requests of end users, the server provides channels to accept user-specified inter-residue distance and contact maps to interactively change the I-TASSER modeling; it also allows users to specify any proteins as template, or to exclude any template proteins during the structure assembly simulations. The structural information could be collected by the users based on experimental evidences or biological insights with the purpose of improving the quality of I-TASSER predictions. The server was evaluated as the best programs for protein structure and function predictions in the recent community-wide CASP experiments. There are currently &gt;20,000 registered scientists from over 100 countries who are using the on-line I-TASSER server.

Guidelines for computer based structural and functional characterization of protein using the I-TASSER pipeline is described. Starting from query protein sequence, 3D models are generated using multiple threading alignments and iterative structural assembly simulations. Functional inferences are thereafter drawn based on matches to proteins with known structure and functions.

Genome sequencing projects have ciphered millions of protein sequence, which require knowledge of their structure and function to improve the ...

Regular Care and Maintenance of a Zebrafish (Danio rerio) Laboratory: An Introduction

This protocol describes regular care and maintenance of a zebrafish laboratory. Zebrafish are now gaining popularity in genetics, pharmacological and behavioural research. As a vertebrate, zebrafish share considerable genetic sequence similarity with humans and are being used as an animal model for various human disease conditions. The advantages of zebrafish in comparison to other common vertebrate models include high fecundity, low maintenance cost, transparent embryos, and rapid development. Due to the spur of interest in zebrafish research, the need to establish and maintain a productive zebrafish housing facility is also increasing. Although literature is available for the maintenance of a zebrafish laboratory, a concise video protocol is lacking. This video illustrates the protocol for regular housing, feeding, breeding and raising of zebrafish larvae. This process will help researchers to understand the natural behaviour and optimal conditions of zebrafish husbandry and hence troubleshoot experimental issues that originate from the fish husbandry conditions. This protocol will be of immense help to researchers planning to establish a zebrafish laboratory, and also to graduate students who are intending to use zebrafish as an animal model.

Regular Care and Maintenance of a Zebrafish Danio rerio Laboratory: An Introduction

This protocol outlines regular maintenance and care to maintain optimal conditions for zebrafish husbandry. The video illustrates the protocol for system maintenance, regular housing, feeding, breeding, and raising of zebrafish larvae.

This protocol describes regular care and maintenance of a zebrafish laboratory. Zebrafish are now gaining popularity in genetics, pharmacological and ...

A Protocol for Phage Display and Affinity Selection Using Recombinant Protein Baits

Using recombinant phage as a scaffold to present various protein portions encoded by a directionally cloned cDNA library to immobilized bait molecules is an efficient means to discover interactions. The technique has largely been used to discover protein-protein interactions but the bait molecule to be challenged need not be restricted to proteins. The protocol presented here has been optimized to allow a modest number of baits to be screened in replicates to maximize the identification of independent clones presenting the same protein. This permits greater confidence that interacting proteins identified are legitimate interactors of the bait molecule. Monitoring the phage titer after each affinity selection round provides information on how the affinity selection is progressing as well as on the efficacy of negative controls. One means of titering the phage, and how and what to prepare in advance to allow this process to progress as efficiently as possible, is presented. Attributes of amplicons retrieved following isolation of independent plaque are highlighted that can be used to ascertain how well the affinity selection has progressed. Trouble shooting techniques to minimize false positives or to bypass persistently recovered phage are explained. Means of reducing viral contamination flare up are discussed.

Phage display is a powerful technique to capture proteins or protein moieties that interact with an immobilized molecule of interest. Once a decision of the type of phage cDNA library to create and screen has been made, the protocol described here permits efficient affinity selection leading to identification of interactors.

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SIVQ-LCM Protocol for the ArcturusXT Instrument

SIVQ-LCM is a new methodology that automates and streamlines the more traditional, user-dependent laser dissection process.&#160;It aims to create an advanced, rapidly customizable laser dissection platform technology. In this report, we describe the integration of the image analysis software Spatially Invariant Vector Quantization (SIVQ) onto the ArcturusXT instrument. The ArcturusXT system contains both an infrared (IR) and ultraviolet (UV) laser, allowing for specific cell or large area dissections. The principal goal is to improve the speed, accuracy, and reproducibility of the laser dissection to increase sample throughput. This novel approach facilitates microdissection of both animal and human tissues in research and clinical workflows.

SIVQ-LCM is an innovative approach that harnesses a computer algorithm, Spatially Invariant Vector Quantization (SIVQ), to drive the laser capture microdissection (LCM) process. The SIVQ-LCM workflow greatly improves the speed and accuracy of microdissection, with applications in both the research and clinical settings.

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A Protocol for Lentiviral Transduction and Downstream Analysis of Intestinal Organoids

Intestinal crypt-villus structures termed organoids, can be kept in sustained culture three dimensionally when supplemented with the appropriate growth factors. Since organoids are highly similar to the original tissue in terms of homeostatic stem cell differentiation, cell polarity and presence of all terminally differentiated cell types known to the adult intestinal epithelium, they serve as an essential resource in experimental research on the epithelium. The possibility to express transgenes or interfering RNA using lentiviral or retroviral vectors in organoids has increased opportunities for functional analysis of the intestinal epithelium and intestinal stem cells, surpassing traditional mouse transgenics in speed and cost. In the current video protocol we show how to utilize transduction of small intestinal organoids with lentiviral vectors illustrated by use of doxycylin inducible transgenes, or IPTG inducible short hairpin RNA for overexpression or gene knockdown. Furthermore, considering organoid culture yields minute cell counts that may even be reduced by experimental treatment, we explain how to process organoids for downstream analysis aimed at quantitative RT-PCR, RNA-microarray and immunohistochemistry. Techniques that enable transgene expression and gene knock down in intestinal organoids contribute to the research potential that these intestinal epithelial structures hold, establishing organoid culture as a new standard in cell culture.

In this video protocol we give a step by step explanation of lentiviral transduction in organoids of primary intestinal epithelium and of processing and downstream analysis of these cultures by quantitative RT-PCR, RNA-microarray and immunohistochemistry.

Intestinal crypt-villus structures termed organoids, can be kept in sustained culture three dimensionally when supplemented with the appropriate growth ...

Laboratory Protocol for Genetic Gut Content Analyses of Aquatic Macroinvertebrates Using Group-specific rDNA Primers

Analyzing food webs is essential for a better understanding of ecosystems. For example, food web interactions can undergo severe changes caused by the invasion of non-indigenous species. However, an exact identification of field predator-prey interactions is difficult in many cases. These analyses are often based on a visual evaluation of gut content or the analysis of stable isotope ratios (&#948;15N and &#948;13C). Such methods require comprehensive knowledge about, respectively, morphologic diversity or isotopic signature from individual prey organisms, leading to obstacles in the exact identification of prey organisms. Visual gut content analyses especially underestimate soft bodied prey organisms, because maceration, ingestion and digestion of prey organisms make identification of specific species difficult. Hence, polymerase chain reaction (PCR) based strategies, for example the use of group-specific primer sets, provide a powerful tool for the investigation of food web interactions. Here, we describe detailed protocols to investigate the gut contents of macroinvertebrate consumers from the field using group-specific primer sets for nuclear ribosomal deoxyribonucleic acid (rDNA). DNA can be extracted either from whole specimens (in the case of small taxa) or out of gut contents of specimens collected in the field. Presence and functional efficiency of the DNA templates need to be confirmed directly from the tested individual using universal primer sets targeting the respective subunit of DNA. We also demonstrate that consumed prey can be determined further down to species level via PCR with unmodified group-specific primers combined with subsequent single strand conformation polymorphism (SSCP) analyses using polyacrylamide gels. Furthermore, we show that the use of different fluorescent dyes as labels enables parallel screening for DNA fragments of different prey groups from multiple gut content samples via automated fragment analysis.

Most common gut content analyses of macroinvertebrates are visual. Requiring intense knowledge about morphological diversity of prey organisms, they miss soft bodied prey and, due to strong comminution of prey, are nearly impossible for some organisms, including amphipods. We provide detailed, novel genetic approaches for macroinvertebrate prey identification in the diet of amphipods.

Analyzing food webs is essential for a better understanding of ecosystems. For example, food web interactions can undergo severe changes caused by the ...