Acute Single and Joint Toxicity Effects of Deltamethrin and Lambda-cyhalothrin on Zebrafish(Danio rerio)

In this research,the single and combined toxicity effects of two commonly used pesticides,lambda-cyhalothrin and deltamethrin,were investigated on zebrafish at 20℃,with a weight of(1±0.1)g and a length of(3.5±0.35)cm.The study revealed that lambda-cyhalothrin exhibited higher toxicity compared to deltamethrin.Additionally,when used together,these pesticides showed significantly increased toxic effects on zebrafish.The 96-h LC 50 values were determined to be 3.059μg/L(confidence limits 0.077-0.351μg/L)for lambda-cyhalothrin and 1.304μg/L(confidence limits;0.046-0.228μg/L)for deltamethrin,both demonstrating a significant positive correlation(P<0.05).These results underscore the importance of regulating and managing pesticide use to safeguard aquatic organisms and uphold environmental sustainability.

Effects of base analogues 5-bromouracil and 6-aminopurine on development of zebrafish Danio Rerio

Zebrafish (Danio rerio) genetic screens allow isolation of a wide array of problems in vertebrate biology. The effects of base analogues 5-bromouracil and 6-aminopurine on the development of zebrafish embryos are reported for the first time in this study. The early development of the zebrafish embryos was little affected by 5-bromouracil and 6-aminopurine, while the late development (organogenesis) was significantly impaired. Embryos exposed to 5-bromouracil mainly showed curled tail, wavy body, golden pigmentation and the mouth with protruding lower jaw. 6-aminopurine-treated embryos had defective anterior structures, curled tails and wavy body. RAPD analysis showed that the majority of 5-bromouracil- and 6-aminopurine-treated larvae and fish shared banding patterns in common with the control, suggesting that most mutagenesis induced by these agents are point mutations. However, some fish derived from 5-bromouracil-treated embryos had golden (gol) pigmentation; and RAPD analysis revealed that their band patterns differed from those of the control. Possibly, 5-bromouracil can occasionally cause relatively extensive changes in the fish genome. The results of this study may provide valuable help for detailed studies of mutagenesis.

In vivo effects of 17-β-estradiol on plasma immunoglobulin levels and leukocyte density in zebrafish Danio rerio

Estradiol, or 17-β-estradiol （E2）, the most potent naturally occurring estrogen, is involved in the hormone-immune system interaction in both mammals and fish. However, in vivo studies are largely limited, and little is known about whether E2 exerts similar effects on both female and male zebrafish （Danio rerio）. Here, we show exposure of both sexes ofD. rerio to 20 nmol/L E2 resulted in a significant increase in Vgl expression, but caused little damage to the hepatocytes, suggesting that this is the optimum E2 concentration. Also, exposure to 20 nmol/L E2 for 20 days caused a marked increase in plasma IgM levels, but had little influence on the peripheral leukocyte density, providing the first evidence of a hormone-immune system interaction in this species.

脱氧鬼臼毒素对斑马鱼(Danio rerio)代谢酶和抗氧化酶活性的影响

为初步探讨脱氧鬼臼毒素（Deoxypodophyllotoxin,DOP）对鱼类的毒性效应,采用静态鱼类急性毒性试验法测定了DOP对斑马鱼（Daniorerio）代谢酶和抗氧化酶活性的影响;参照DOP的96hLC50值,设定4个浓度（0.5、1.0、2.0、4.0mg·L-1）处理斑马鱼,48h后测定斑马鱼肌肉组织腺苷三磷酸酶（ATPase）、过氧化氢酶（CAT）和超氧化物歧化酶（SOD）活性.结果表明,DOP对斑马鱼96hLC50值为3.49mg·L-1,安全浓度为0.36mg·L-1.DOP在0.5~4.0mg·L-1对斑马鱼肌肉总ATPase、Na＋-K＋-ATPase和Ca2＋-ATPase的作用趋势均表现为：1.0和2.0mg·L-1显著激活（p〈0.05,p〈0.01）;4.0mg·L-1显著抑制（p〈0.05）,抑制率分别为24.4%、12.3%和33.8%.DOP在0.5~4.0mg·L-1对斑马鱼肌肉抗氧化酶的作用趋势与对ATPase的作用趋势一致,表现为：1.0、2.0mg·L-1DOP对SOD和CAT均表现为显著激活（p〈0.05,p〈0.01）;4.0mg·L-1DOP对SOD和CAT均表现为显著抑制（p〈0.05）,抑制率分别为34.1%和31.9%.以上结果表明,DOP对斑马鱼为中等毒性;斑马鱼肌肉组织ATPase、CAT和SOD可能是脱氧鬼臼毒素的作用标靶之一.

4-壬基酚对斑马鱼(Danio rerio)胚胎/仔鱼的毒性效应

4-壬基酚(4-NP)作为一种稳定的环境内分泌干扰物,会对生物体的生长发育造成影响。以斑马鱼(Danio rerio)胚胎为供试体,研究4-壬基酚对斑马鱼胚胎生长发育的毒性效应。斑马鱼胚胎被暴露在一系列浓度的4-壬基酚溶液中(2.0、5.0、10.0、25.0、50.0和125.0μg·L-1),暴露120 h后空白组初孵仔鱼因饥饿出现死亡即停止实验。记录暴露120 h内斑马鱼胚胎的死亡数、孵化数,畸形数、仔鱼体长及30 s心跳数。结果表明,4-壬基酚对斑马鱼胚胎48、72和96 h的半致死浓度(LC50)分别为131.4、47.2和26.8μg·L-1;125.0μg·L-1的4-壬基酚对斑马鱼胚胎的高致死效应使其孵化率显著降低;与空白对照组相比,4-壬基酚的暴露可显著提高斑马鱼胚胎尾部畸形率和仔鱼的心包囊肿率,其中斑马鱼胚胎尾部畸形率随处理浓度的增加而增加,呈正剂量-效应关系;经4-壬基酚暴露处理的斑马鱼仔鱼的体长及30 s心跳数较空白对照组均显著下降。2.0μg·L-14-壬基酚对斑马鱼胚胎及仔鱼即具有致畸和致死效应,对其胚胎的发育有不利影响。

伊维菌素对斑马鱼(Danio rerio)生理生化特性的影响

为探讨水产常用抗寄生虫药物伊维菌素（IVM）对鱼类的毒性效应，参考IVM对斑马鱼的96h—LC50值，设定了7μg／L、14μg/L及21μg／L3个处理组，并以0．021％乙醇为试剂对照组，采用96h半静水式毒性试验测定了MM对斑马鱼（Dartiorer／o）头部乳酸脱氢酶（LDH）、乙酰胆碱酯酶（AChE）和碱性磷酸酶（ALP）以及肌肉组织中超氧化物歧化酶（SOD）、丙二醛（MDA）和ALP等生理生化指标的影响。结果表明：IVM对斑马鱼肌肉SOD活性的影响总体表现为低质量浓度抑制，高质量浓度先诱导后抑制；MDA含量在低质量浓度作用下8～12h内显著高于对照组（P≤0．05），而在较高质量浓度下先受到显著抑制（P〈0．05），虽然后期有一定的恢复，但总体仍低于对照组；IVM对AChE活性影响在短期内并不明显，但在96h时最高质量浓度组的1VM对AChE产生了55．2％的抑制；头部LDH活性只在8～24h内受到不同程度的影响，之后便逐渐恢复；头部ALP活性在较高质量浓度作用12—24h内受到一定的抑制（P〈0．05），而肌肉ALP活性与对照组相比无显著差异（P〉0．05），表明头部ALP活性比肌肉敏感。

三甲基氯化锡对斑马鱼(Danio rerio)生理生化特性的影响

为初步探讨三甲基氯化锡(trimethyltin chloride,TMT)对鱼类的毒性效应以及评价环境中TMT的安全性,采用静态鱼类急性毒性试验法测定了TMT对斑马鱼(Danio rerio)生理生化指标的影响;参考TMT的96h-LC50值,设定3个浓度(0.39、0.78和1.17mg·L-1)处理斑马鱼,测定了72h内鳃Na+,K+-ATPase、头部乙酰胆碱酯酶(AchE)和肌肉超氧化物歧化酶(SOD)的活性变化。结果表明,TMT对斑马鱼的96h-LC50值为2.35mg·L-1,安全浓度为0.23mg·L-1。TMT对斑马鱼鳃Na+,K+-AT-Pase有明显的抑制作用。当TMT浓度≥0.78mg·L-1时酶活性被完全抑制(抑制率>32%),低浓度组0.39mg·L-1酶活性先表现为抑制,24h后有恢复到对照组水平的趋势。TMT对斑马鱼头部AchE活性表现为抑制,随着暴露时间的延长和药物浓度的增加,酶活性抑制增强。由于鱼脑AchE的高波动性,实验中只有最高浓度组1.17mg·L-1的鱼受到明显的抑制(p<0.05)。TMT对斑马鱼肌肉SOD活性总体表现为先激活后下降趋势,TMT浓度越高酶活性激活越快,下降也越快,其中0.39、0.78和1.17mg·L-1组活性分别在48、24和12h激活到最大,SOD活性分别为对照组的153%、145%和153%。以上结果表明,TMT对斑马鱼属于高毒。斑马鱼鳃Na+,K+-ATPase是三甲基氯化锡的作用标靶,可以作为TMT对斑马鱼毒性效应的敏感指标。

Study on the Acute Toxicity and Genetics Toxicity of Bensulfuronk-methyl on Danio rerio

[Objective] The aim was to study the effect of bensulfuron-methyl herbicide on acute toxicity and genetics toxicity of Danio redo. [ Method] Median lethal concentration was calculated by acute toxicity test, and analyzing the herbicide whether existing in potential toxicity to aquatic organisms or not. Based on the study of acute toxicity, genetics toxicity was carried out, by calculating the micronucleus rate to judge bensulfuron-methyl herbicide whether existing in potential toxicity or not. [ Result ] The LD5o （24 h and 48 h） of bensulfuron-methyl herbicide are 0.698 ml/L and 0.637 ml/L respectively, the safe concentration was 0.159 ml/L. The results on the effects of micronucleus （MN） in erythrocytes of Danio redo induced by bensulfuron-methyl at different times and different concentrations showed that the MN rate of control group was 0.010 3%, the highest MN rate of experimental group reached to 0. 372%, it also indicated that bensulfuron-methyl herbicide had genetics toxicity to Danio redo. At the same detection time, there was dose-effect relationship of MN rate in erythrocytes between treatment and control groups with different concentrations. In the same treatment group, the MN rate in erythrocytes reached to peak value at 24 h, and decreased at 48 h and 72 h with the infection time was prolonged. [ Conclusion ] The study provides some basis for scientifically selecting and reasonably using herbicide.

整体原位杂交法研究斑马鱼(Danio rerio)胚胎发育过程中胸苷酸合成酶(TS)的表达

收集不同发育时期的斑马鱼胚胎,制备DIG标记的TS反义RNA探针,采用整体原位杂交方法研究胸苷酸合成酶(TS)基因在斑马鱼胚胎发育各期的时空表达状况。结果表明,在所取样的各个阶段,TS基因均有转录,但其部位不同,中囊胚过渡前后mRNA显现的部位仅存在于受精卵的动物极,10hpf时存在于整个胚胎的外围,至24hpf后集中到头部及其躯干部。112hpf在心脏部位强表达,其余部位表达相对较弱。

厚朴酚对斑马鱼（Danio rerio）的急性毒性病理损伤评估

【目的】针对和厚朴酚(Honokiol)对斑马鱼(Danio rerio)的毒性损伤,采用半静态急性毒性实验将斑马鱼浸泡于和厚朴酚溶液中,研究和厚朴酚对斑马鱼的毒性作用及组织病理学影响.【方法】将105尾健康斑马鱼随机浸泡于7个试验组中(n=15):对照组(曝气自来水)、助溶剂乙醇组(1%体积比)和5个和厚朴酚浓度组(0.1、0.2、0.4、0.6、和0.8 mg/L),对斑马鱼的临床症状、大体病变、死亡率以及组织病理学进行判定,并结合组织病理评分系统评价各组斑马鱼的损伤情况,评估和厚朴酚的毒性.[结果]不同浓度和厚朴酚组浸泡的斑马鱼在96 h内出现不同程度死亡,其96 h半数致死浓度(LC50)为(0.530±0.014)mg/L,72 h-LC50为(0.679±0.013)mg/L,48 h-LC50为(0.758±0.012)mg/L,24 h-LC50为(0.816±0.01)mg/L,而安全浓度(SC)为(0.264±0.003)mg/L.此外,在设定的浓度范围内,和厚朴酚未造成斑马鱼出现明显的临床及大体病理变化.组织病理学显示,和厚朴酚浸泡后主要导致鳃和脑充血,此外还可见鳃呼吸上皮坏死等,其余组织与对照组相比无明显病变.【结论】和厚朴酚对于斑马鱼存在一定毒性,鳃和脑可能是和厚朴酚对鱼类的主要毒性靶器官.

斑马鱼(Danio rerio)mapk1基因对tp53基因调控研究

旨在研究斑马鱼(Danio rerio)mapk1基因对tp53基因的调控作用。通过生信网站分析斑马鱼tp53启动子序列与mapk1基因CDS序列,构建斑马鱼tp53启动子荧光素酶报告基因质粒pGL3-tp53-Luc和mapk1表达质粒pCMV-Tag2B-mapk1。利用Luciferase实验验证tp53启动子报告基因的活性,以及mapk1基因对tp53基因的活性影响。结果显示,斑马鱼tp53基因启动子区无CpG岛位点,包含Oct-1(TATGTAAAGC)、Sp-1(AGATCCCGCC)、c-Jun(CTGACGTCAC)、CREB(CTGACGTCAC)、CREBP1(CTGACGTCAC)、NF-kappa B1(AGGGGAATCC)和RAR-alpha1(TTGAACTTTT)共7个转录因子结合位点;斑马鱼与人和小鼠MAPK1氨基酸的一致性分别为91.33%和90.79%。pGL3-tp53-Luc在哺乳动物细胞系和鱼类细胞系中均具有很高的活性,分别是对照组的17倍和9倍。在HEK293T细胞中过表达pCMV-Tag2B-mapk1质粒后pGL3-tp53-Luc的luciferase活性是对照组的3倍左右。实验验证了斑马鱼mapk1基因可促进tp53基因的表达。

再生水景观利用对斑马鱼(Danio rerio)下丘脑-垂体-性腺(HPG)轴相关基因转录水平的影响

再生水对水体生物具有潜在的危害。为了评估再生水对水体生物的早期分子毒理效应,采用荧光定量多聚酶链式反应(polymerase chain reaction,PCR)技术分析再生水对斑马鱼下丘脑-垂体-性腺(hypothalamus-pituitary-gonadal,HPG)轴相关基因转录水平的影响。再生水暴露后,斑马鱼体长、体质量、生长状况因子(condition factor,K)、脑指数(brain-somatic index,BSI)和性腺指数(gonadosomatic index,GSI)无显著改变。再生水暴露7 d引起雄性斑马鱼脑雄激素受体(androgen receptor,Ar)、雌激素受体1(estrogen receptor 1,Esr1)、卵泡刺激素β多肽(follicle stimulating hormone beta polypeptide,Fshb)、黄体生成素β多肽(luteinizing hormone beta polypeptide,Lhb)、促性腺激素释放激素(gonadotropin-releasing hormone 2,Gnrh2)和促性腺激素释放激素(gonado-tropin-releasing hormone 3,Gnrh3)基因的转录水平显著下调(P<0.05),并引起雌性斑马鱼脑Gnrh3基因转录水平显著上调(P<0.05)。再生水暴露7 d导致类固醇激素合成通路下游基因如Ar、Esr1、卵巢芳香化酶(ovarian cytochrome P450 aromatase,cyp19ala)、3β-羟基类固醇脱氢酶(3β-hydroxysteroid dehydrogenase,hsd3b)、17β-羟化类固醇脱氢酶3(17β-hydroxysteroid dehydro-genase type 3,hsd17b3)和20β-羟化类固醇脱氢酶(20β-hydroxysteroid dehydrogenase,hsd20b)在雄性斑马鱼睾丸中表达水平显著减少(P<0.05);相反,雌性斑马鱼卵巢Esr1和11β-羟化酶(11β-hydroxylase,cyp11b)基因转录水平显著增加(P<0.05)。再生水对斑马鱼暴露14 d后,雄性斑马鱼脑Esr1、Fshb和Lhb基因表达水平显著下调(P<0.05),睾丸Ar、Esr1、类固醇源性急性调节蛋白(steroidogenic acute regulatory,star)、cyp19a1a、11β-羟化类固醇脱氢酶2(11β-hydroxysteroid dehydrogenase 2,hsd11b2)、hsd20b和hsd17b3基因转录水平也显著降低(P<0.05)。然而再生水暴露14 d显著上调了雌性斑马鱼卵巢Esr1、孕激素受体(progesterone receptor,pgr)、cyp19a1a、hsd3b、hsd17b3和star基因转录水平(P<0.05),并且下调了脑Gnrh3和Fshb的转录水平(P<0.05)。综上所述,本研究结果表明再生水显著影响了斑马鱼HPG轴相关基因转录水平,具有性别和暴露时间差异性,为再生水对斑马鱼生殖系统的影响提供了新的见解。

Identification of Z-OTU protein during zebrafish oogenesis and early embryogenesis

Zebrafish（Danio rerio） Z-OTU,containing OTU and TUDOR domains,was predicted to be a member of OTU-related protease,a family of the deubiquitylating enzymes（DUBs）.A previous report from our laboratory clearly describes the expression patterns of z-otu mRNA.Here,we characterized the Z-OTU protein during zebrafish oogenesis and early embryogenesis.After prokaryotic expression,the recombinant protein of the OTU domain and GST was purified and injected into rabbits to obtain the polyclonal antibody-anti-Z-OTU,which was used for immunohistochemistry in zebrafish ovaries and embryos.Interestingly,obvious differences existed between the expression patterns of z-otu mRNA and its protein during oogenesis and early embryogenesis.In stage I oocytes,z-otu mRNA was detected in cytoplasm while its protein existed in the germinal vesicle.In addition,its protein was distributed during entire oogenesis,while mRNA was not detected in oocytes at stage IV or mature oocytes.The z-otu mRNA disappeared after midblastula transition（MBT） and its protein gradually decreased after this stage.We inferred that Z-OTU protein,like other OTU-related protease with DUB activity,was required for germinal vesicle breakdown of oocytes during meiosis,germinal vesicle migration,and embryo cleavage maintenance.

Toxic effects of perfluorononanoic acid on the development of Zebrafish(Danio rerio) embryos

Perfluorononanoic acid（PFNA） is a nine-carbon perfluoroalkyl acid widely used in industrial and domestic products. It is a persistent organic pollutant found in the environment as well as in the tissues of humans and wildlife. There is a concern that this chemical might be a developmental toxicant and teratogen in various ecosystems. In the present study,the toxic effects of PFNA were evaluated in zebrafish（Danio rerio） embryos. One hour post-fertilization embryos were treated with 0, 25, 50, 100, 200, 300, 350, and 400 μmol/L PFNA for 96 hr in 6-well plates. Developmental phenotypes and hatching rates were observed and recorded. Nineteen genes related to oxidative stress and lipid metabolism were examined using Quantitative RT-PCR and confirmed by whole mount in situ hybridization（WISH）. Results showed that PFNA delayed the development of zebrafish embryos, reduced the hatching rate, and caused ventricular edema and malformation of the spine. In addition, the amount of reactive oxygen species in the embryo bodies increased significantly after exposure to PFNA compared with that of the control group. The Quantitative RT-PCR and WISH experiments demonstrated that m RNA expression of the lfabp and ucp2 genes increased significantly while that of sod1 and mt-nd1 decreased significantly after PFNA exposure. The m RNA expression levels of gpx1 and mt-atp6 decreased significantly in the high concentration group. However, the m RNA expression levels of both ppara and pparg did not show any significant variation after exposure. These findings suggest that PFNA affected the development of zebrafish embryos at relatively low concentrations.

Dynamic interaction of neutrophils and RFP-labelled Vibrio parahaemolyticus in zebrafish(Danio rerio)

Vibrio parahaemolyticus(Vp)is an aquatic zoonotic pathogen that causes vibriosis in marine animals as well as sepsis,gastroenteritis and wound infection in human.In vertebrates,the innate immune system plays a critical defense mechanism against Vp infection including transmigration of neutrophils.In this study,we have examined the genetic recombination and infectious process of Vp in the zebrafish(Danio rerio),a vertebrate model system extensively used for studying host-pathogen interactions.A pathogenic Vp strain,Vp57,tagged with red fluorescent protein(RFP)(Vp57^(RFP))was introduced into larval zebrafish at 3 days post fertilization(dpf),in which the innate immunity is present whereas the adaptive immunity has not yet developed.Vp57 and Vp57^(RFP)showed similar LD50 and induced similar symptoms and pathological changes in the hosts.We microinjected 579 colony-forming units(CFU)Vp57^(RFP)into the zebrafish caudal vein,and observed that neutrophils were recruited to the injection site and within 3 h post infection(hpi)Vp57^(RFP)were mainly distributed in the tail,eyes,heart and optic vesicle.After 3 hpi,the fish died with slight spine bending.Several Vp57^(RFP)were also detected in somites,the phagocytosis of neutrophils was activated through the progress of bacterial infections.We found that chemotaxis and phagocytosis of neutrophils occurs when zebrafish is infected by Vp57^(RFP),whereas Vp57^(RFP)can escape from neutrophils and colonize other remote regions using the blood circulation system.

Daily variation in the shoaling behavior of zebrafish Danio rerio

Shoaling behavior provides numerous fitness benefits for fish, including enhanced access to mates, increased success in foraging and protection from predators. We were interested in determining whether shoaling intensity differed throughout the day. To do this we kept adult zebrafish Danio rerio in different lighting conditions for 10 days： ＂Normal＂ （12：12LD, lights on at 0800 hrs）, ＂Reverse＂ （12：12LD, lights on at 2000 hrs）, DD, or LL, and then observed the shoaling behavior at different times during the day. Our findings suggest that daily variations exist in shoaling behavior, with mean shoaling times for fish from the ＇normal＇ group being the lowest at the mid-point of the dark phase in the fish＇s subjective day （00：00 hrs）, then rising signifi- cantly throughout the day, reaching their highest intensity at 20：00 hrs （lights out）. Fish from the ＂reverse＂ LD cycle （lights on at 20：00 hrs） showed differences in the mean shoaling times at different times of day, but did not show a gradual increase in shoaling throughout their subjective day. Fish from the DD and LL groups did not show significant differences in the mean shoaling values at different times of day, suggesting that the differences observed in LD fish may not represent circadian rhythms. Therefore, these results demonstrate the existence of daily variations in the shoaling behavior of fish and suggest that environmental cues in the form of light/dark cycles play an important role in regulating these variations [Current Zoology 58 （1）： 129-137, 2012].

Mepanipyrim induces cardiotoxicity of zebrafish(Danio rerio) larvae via promoting AhR-regulated COX expression pathway

The wide use of pesticides has seriously threatened human health and the survival of beneficial organisms. The fungicide mepanipyrim is widely used in viticulture practices. Studies of mepanipyrim-induced toxicity in organisms are still scarce, especially studies on cardiotoxicity. In this study, we aimed to investigate mepanipyrim-induced cardiotoxicity in zebrafish(Danio rerio) larvae. We found that mepanipyrim could induce cardiotoxicity by altering the heart rate and cardiomyocyte diameter of larvae. Meanwhile, RNA sequencing and RT-qPCR data indicated that mepanipyrim exposure could dramatically alter the m RNA expression of calcium signaling pathway-, cardiac muscle contraction-, and oxidative respiratory chain-related genes. Interestingly, by the CALUX cell bioassay, we found that most cytochrome c oxidase(COX) family genes exhibited potential AhR-regulated activity, suggesting that mepanipyrim induced cardiotoxicity via a novel AhR-regulated manner in larvae.Additionally, the AhR antagonist CH_(2)23191 could effectively prevent mepanipyrim-induced cardiotoxicity in zebrafish larvae. In conclusion, the AhR agonist mepanipyrim could induce cardiotoxicity in a novel unreported AhR-regulated manner, which could specifically affect the expression of COX family genes involved in the mitochondrial oxidative respiratory chain. Our data will help explain the toxic effects of mepanipyrim on organisms and provide new insight into the AhR agonistic activity pesticide-induced cardiotoxicity.

Cloning and Expression of BTB/POZ-Domain from Zebrafish gcl (Germ Cell-Less), and Appraisement of Its Polyclonal-Antibody

In this study, a recombinant pET28c-gBTB/POZ was constructed by cloning the sequence of the BTB/POZ domain of the zebrafish gcl （germ cell-less） into the expression vector pET28c, and pET28c-gBTB/POZ was transformed into BL21（DE3） pLysS strain to express the fusion protein for the preparation of antibody. Polyclonal-antibody against the GCL-BTB/POZ domain was prepared by immunizing rabbit with the fusion protein, and the Western Blot and immuno-histochemical analysis were performed to detect the quantity of the polyclonal-antibody. The result indicates that the polyclonal-antibodies were of good quantity and specification. Further studies will be performed to demonstrate the function and expression pattern of the GCL protein during the development process of zebrafish with the polyclonal-antibody.

Daily shoaling patterns in the zebrafish Danio rerio

Shoaling intensity in zebrafish Danio rerio is believed to vary throughout subjective day and night hours. This experiment examines long term variations in shoaling behavior. Adult zebrafish Dan io rerio were maintained under a 12：12 LD cycle （with dim red light serving as reduced visibility during subjective dark hours）, and their shoaling behavior was monitored every hour for a three-day period of time. Our results show that zebrafish perform shoaling behavior throughout subjective day and under reduced visibility conditions, although mean shoaling times during the light phase were significantly higher than mean shoaling times during the dark phase. However, on the 3^rd day of the experiment, mean shoaling times during the subjective night had increased and mean shoaling times during the subjective day had decreased. This shift in intensity was not seen on the first two days of the study, and may represent the influence of experience on the behavior of the test fish. We believe this study shows that shoaling behavior changes with light/dark cycles and that fish shoal even during reduced visibility conditions.

Systematic genome editing of the genes spanning an entire chromosome by CRISPR/Cas9 in a vertebrate——zebrafish (Danio rerio)

Deciphering the biological functions of each gene in the genome is fundamental for understanding the molecular mechanisms underlying normal development, physiology,and behavior, as well as diseases. One common approach to determine gene function is to disrupt individual genes and assess the consequences. Zebrafish (Danio rerio) has been gaining popularity as a model organism to analyze gene function. This is particularly true in China.