广东农业科学  2024, Vol. 51 Issue (4): 35-44   DOI: 10.16768/j.issn.1004-874X.2024.04.003.
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文章信息

引用本文
成果, 温彬, 高建忠, 陈再忠. 七彩神仙鱼催乳素基因的克隆、定位及表达分析[J]. 广东农业科学, 2024, 51(4): 35-44.   DOI: 10.16768/j.issn.1004-874X.2024.04.003
CHENG Guo, WEN Bin, GAO Jianzhong, CHEN Zaizhong. Cloning, Localization and Expression of Prolactin Gene in Discus Fish (Symphysodon aequifasciatus)[J]. Guangdong Agricultural Sciences, 2024, 51(4): 35-44.   DOI: 10.16768/j.issn.1004-874X.2024.04.003

基金项目

上海市自然科学基金(20ZR1423600);上海海洋大学科技发展专项基金(A2-2006-22-2002);国家自然科学基金(31902376)

作者简介

成果(1998—),女,在读硕士生,研究方向为特色鱼类养殖,E-mail:1049122745@qq.com; 温彬,博士,上海海洋大学水产与生命学院副教授,硕士生导师。先后入选上海市青年科技英才扬帆计划、东方英才计划青年项目(原上海市青年拔尖人才),主持国家自然科学基金面上项目和青年项目、中国博士后科学基金、上海市科委和教委等多个项目。主要从事水产养殖生态学与养殖模式、特色鱼类养殖研究。以第一或通信作者在《 Aquaculture》《 Journal of Hazardous Materials》《 Science of the Total Environment》等水产和生态环境著名期刊发表论文50余篇,其中ESI高被引论文8篇,单篇最高他引近300次,获上海水产学会优秀学术论文一等奖1项、二等奖2项,授权专利5件,副主编专著2部。兼任《广东农业科学》《 iMeta》》《 Eco-Environment & Health》《 Agriculture Communications》《 Modern Agriculture》等学术期刊青年编委。指导研究生多次荣获国家奖学金,指导多名本科生以第一作者发表高水平论文,并获全国大学生生命科学竞赛特等奖等10余项。担任本期“观赏鱼遗传育种与健康养殖”专题的客座主编。.

通讯作者

温彬(1987—),男,博士,副教授,研究方向为特色鱼类养殖,E-mail:bwen@shou.edu.cn.

文章历史

收稿日期:2023-11-20
七彩神仙鱼催乳素基因的克隆、定位及表达分析
成果 , 温彬 , 高建忠 , 陈再忠     
上海海洋大学水产与生命学院/农业农村部淡水水产种质资源重点实验室/水产种质资源发掘与利用教育部重点实验室/水产科学国家级实验教学示范中心,上海 201306
摘要:【目的】 七彩神仙鱼(Symphysodon aequifasciatus)具有特殊的亲代抚育行为,克隆并定位七彩神仙鱼催乳素基因,分析其在亲代抚育中的表达模式,为理解催乳素在七彩神仙鱼亲代抚育中的作用提供依据。【方法】 通过BLASTP对七彩神仙鱼全基因组进行分析,鉴定出1个催乳素基因,命名为dfprl。基于dfprl基因的CDS区,设计克隆和PCR引物,通过RACE技术克隆获得dfprl基因全长,并利用生物信息学对dfprl基因进行结构分析,对其氨基酸序列进行理化性质和进化分析。对不同抚育阶段七彩神仙鱼的脑、性腺和皮肤进行转录组分析,探究dfprl基因在亲代抚育中的表达特征,并利用原位杂交技术对dfprl基因在七彩神仙鱼皮肤中的表达进行定位。【结果】 dfprl全长为1 282 bp,cDNA序列开放阅读框长度为639 bp,共编码212个氨基酸,5'-UTR为309 bp,3'-UTR为334 bp。dfprl蛋白存在PRL家族的典型结构域Hormone_1,dfprl蛋白与慈鲷科其他鱼类PRL蛋白相似性较高,与尼加拉瓜湖始丽鱼(Archocentrus centrarchus)对应的氨基酸序列同源性最高、为96.70%。亲鱼进入抚育阶段后,dfprl在性腺和皮肤中的表达水平逐渐上升,抚育结束时表达水平下降。原位杂交结果显示,dfprl在皮肤粘液细胞中表达,且与七彩神仙鱼催乳素受体(dfprlr)表达位点重叠,在抚育早期阶段高表达。【结论】 七彩神仙鱼dfprl基因高度保守,存在稳定的Hormone_1结构域。七彩神仙鱼dfprl基因在亲代抚育阶段的皮肤中高表达,且在亲代抚育阶段的皮肤粘液细胞中与dfprlr表达位点重合,表明dfprl可能通过作用于dfprlr进而促进七彩神仙鱼独特抚育行为的发生。
关键词七彩神仙鱼    催乳素    亲代抚育    皮肤粘液细胞    基因克隆    
Cloning, Localization and Expression of Prolactin Gene in Discus Fish (Symphysodon aequifasciatus)
CHENG Guo , WEN Bin , GAO Jianzhong , CHEN Zaizhong     
College of Fisheries and Life Science, Shanghai Ocean University/Key Laboratory of Freshwater Aquatic Genetic Resources, Ministry of Agriculture and Rural Affairs/Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources, Ministry of Education/National Demonstration Centre for Experimental Fisheries Science Education, Shanghai 201306, China
Abstract: 【Objective】 Discus fish (Symphysodon aequifasciatus) has special parental care behavior. In the study, prolactin (PRL) gene from discus fish was cloned and localized and its expression pattern during parental care was analyzed, with an aim to provide a basis for understanding the function of PRL in parental care of discus fish. 【Method】 A prolactin gene named dfprl was identified by analyzing the whole genome data of the discus fish through BLASTP. The CDS region of dfprl genes were used to design the primer of gene cloing and PCR. The full length of dfprl gene was cloned by RACE technology, and the structure of dfprl gene was analyzed by bioinformatics and its amino acid sequence was analyzed by physicochemical properties and phyletic evolution. Transcriptome sequencing was performed on brain, gonad and skin of discus fish at different rearing stages to explore the expression pattern of dfprl gene during parental care. The dfprl gene in the skin of discus fish was located by paraffin-fluorescence probe-FISH. 【Result】 The full length of dfprl was 1 282 bp, with 639 bp cDNA sequence encoding 212 amino acids, 309 bp 5'-UTR and 334 bp 3'-UTR. The dfprl protein has the typical domain of PRL family, the Hormone_1 domain. dfprl protein is highly similar to PRL protein of other Cichlidae, and the amino acid sequence homology of dfprl with Archocentrus centrarchus prolactin (AcPRL) was the highest (96.70%). The expression level of dfprl in gonad and skin increased gradually after the parent fish entered the rearing stage, and decreased at the end of the rearing stage. The paraffin-fluorescence probe-FISH results showed that dfprl was expressed in skin mucous cells, and it was coincident with the expression site of prolactin receptor (dfprlr) and was highly expressed in the early stage of parental care. 【Conclusion】 The dfprl gene is highly conserved and has stable Hormone _1 domain. dfprl gene was highly expressed in the skin during the parental care stage, . and the expression sites of dfprl and dfprlr overlapped in skin mucous cells during the parental care stage of discus fish, suggesting that dfprl might be involved in the occurrence of unique parental care behavior of discus fish.
Key words: Symphysodon aequifasciatus    prolactin    parental care    skin mucus cell    gene clone    

【研究意义】七彩神仙鱼(Symphysodon aequifasciatus)隶属于盘丽鱼属,原产自亚马逊河流域,其体色艳丽,具有极高的观赏价值,因此被誉为“观赏鱼之王” [1-2]。七彩神仙鱼具有特殊的亲代抚育行为,可利用皮肤细胞分泌粘液喂养子代长达1个月,在行为模式上与哺乳相似[1-5]。亲代抚育行为的发生涉及大脑[6]到生殖器官[7]多层次生理变化,下丘脑-垂体-性腺(HPG)轴对其具有重要影响[8-9]。探究催乳素(Prolactin, PRL)在七彩神仙鱼亲代抚育行为发生中的潜在功能具有重要意义。【前人研究进展】PRL是一种主要由垂体前叶泌乳细胞合成和分泌的多肽激素[10],通过与催乳素受体(Prolactin receptor, PRLR)结合来发挥其作用。最初因PRL能诱导鸽子分泌乳汁而被鉴定,随后因其在哺乳动物中能够刺激乳腺分泌乳汁而被命名[11]。PRL在脊椎动物(包括鸟类、哺乳动物和鱼类[12-15])的亲代行为中起重要作用,参与渗透调节、哺乳、繁殖、发育和生长、内分泌和代谢、免疫调节等生命活动[14,16-24]。在鸟类中,PRL是鸟类亲代行为发生和维持的基础[17,25];在鱼类中,PRL和雌激素共同促进慈鲷鱼类口孵行为的发生[26]。外源注射PRL可增加叉尾斗鱼(Macropodus opercularis)粘液分泌量,并刺激粘液细胞的增殖,促进筑巢行为[27-28]。对蓝鳃太阳鱼(Lepomis macrochirus)和三刺棘鱼(Gasterosteus aculeatus)进行PRL抑制后,亲鱼巢扇行为明显减少[29-30]。雄性蓝鳃太阳鱼经PRL抑制剂处理后,对捕食者的攻击性减少,对仔鱼的保护和防御行为减少[30]。注射PRL后的七彩神仙鱼亲鱼抚育行为增加,推测PRL可能在七彩神仙鱼亲代抚育行为中起作用[31]。【本研究切入点】包括PRL在内的多种循环激素能够促进亲代抚育行为的发生,但相关研究主要集中在哺乳动物和鸟类,对PRL在鱼类亲代抚育行为中的作用研究较少。【拟解决的关键问题】本研究从七彩神仙鱼中鉴定并克隆PRL基因,命名为dfprl,分析其在不同抚育阶段七彩神仙鱼的脑、性腺和皮肤组织中的表达,并在皮肤组织中对dfprl基因及其受体基因(dfprlr)进行双探针原位杂交,揭示dfprl在七彩神仙鱼亲代抚育中的潜在功能,为提高七彩神仙鱼人工繁育效率提供科学依据。

1 材料与方法 1.1 试验材料

供试的七彩神仙鱼由上海海洋大学滨海养殖基地提供,经上海海洋大学动物护理和使用委员会批准(SHOU-DW-2021-026)后使用。挑选非繁殖期(NB)、产卵期(S)、抚育1 d(P1)、抚育7 d(P7)、非抚育期(NP)等不同繁殖阶段(表 1)的七彩神仙鱼各3对,实验用鱼形体健康、规格一致(体长11.0±1.5 cm),保持养殖条件相同(28.0±0.5 ℃,pH 7.8±0.5,DO>6.0 mg/L)。

表 1 七彩神仙鱼繁殖阶段划分 Table 1 Division of breeding stages of discus fish

1.2 试验方法

1.2.1 样品采集 于2022年8—9月在上海海洋大学滨海养殖基地进行七彩神仙鱼养殖试验,在养殖过程中分别采集上述5个时期共15对七彩神仙鱼的脑、性腺和皮肤组织(亲鱼进入不同繁殖阶段的第1天上午10:00取样),置于无酶管中,在液氮中冷冻,-80 ℃下保存,用于转录组测序分析。另采集皮肤组织置于15 mL装满原位杂交固定液的无酶管中,4 ℃下保存备用。

1.2.2 总RNA提取和cDNA合成 使用TRIzol 〔生工生物工程(上海)股份有限公司〕提取各组织中的总RNA,经NanoPhotometer和NanoDrop评估,每个样品的总RNA量为1 μg,完整性数>7.0。选取光密度OD260/280为1.8~2.2的样品等量混合,通过1% MOPs琼脂糖凝胶进行电泳以及微量核酸蛋白测定仪进行定性和定量检测。使用DNase Ⅰ(上海碧云天生物技术有限公司)去除RNA中残留的DNA,以1 μg总RNA为模板反转录成cDNA,将cDNA保存于-20 ℃下。

1.2.3 基因筛选和序列验证 采用七彩神仙鱼全基因组数据(GenBank登录号:PRJNA863920),以Ensembl数据库下载的尼罗罗非鱼(Oreochromis niloticus)和人类(Homo sapiens)的PRL蛋白为参考序列,通过BLASTP(2.9.0)(E<0.001)对七彩神仙鱼全基因组进行比对[32-33]。为确认PLR存在1个或多个结构域,使用PFAM和SMART对所有基于BLASTP的候选序列进一步筛选。将两种方法获得的基因剔除冗余,从七彩神仙鱼基因组中鉴定出PRL基因,命名为dfprl

选取dfprl基因的CDS区,使用Primer Premier 5.0设计PCR引物(表 2),由上海生工生物工程股份有限公司合成。以七彩神仙鱼皮肤cDNA作为模板,使用C1000 Touch™ PCR仪(Bio-Rad,美国)对dfprl进行PCR扩增。反应体系25 μL:Mix(TSE101)22 μL、cDNA 1 μL、dfprl-O-F 1 μL、dfprl-O-R 1 μL。反应条件:98 ℃ 2 min;98 ℃ 10 s、56 ℃ 30 s、72 ℃ 10 s,10个循环;98 ℃ 10 s、51 ℃ 30 s、72 ℃ 10 s,25个循环;72 ℃ 1 min。产物经1% 琼脂糖凝胶电泳,胶回收后送至上海生工生物工程股份有限公司进行测序。

表 2 引物序列信息 Table 2 Primer sequence information

1.2.4 dfprl基因的3'-RACE和5'-RACE克隆 根据dfprl基因的CDS区,使用Primer Premier 5.0设计3'-RACE特异性巢式引物、5'-RACE特异性巢式引物和5'-RACE特异性反转录引物(表 2)。分别使用3'-RACE Kit、5'-RACE Kit〔生工生物工程(上海)股份有限公司〕对dfprl基因3' 末端、5' 末端进行扩增。

1.2.5 生物信息学分析 使用NCBI的ORF Finder(https://www.ncbi.nlm.nih.gov/orffinder/)查找dfprl基因的ORF区,获得相应的氨基酸序列。通过在线软件ExPASy-ProtParam(http://web.expasy.org/computepi/)预测dfprl的氨基酸数、分子量、等电点和亲水性等信息。由SignalP4.1(http://www.cbs.dtu.dk/services/SignalP/)和TMHMM2.0(http://www.cbs.dtu.dk/services/ TMHMM)预测信号肽和跨膜结构域。运用SOPMA(https://npsa-pbil.ibcp.fr/)和SWISSMODEL(https://swissmodel.expasy.org/)进行蛋白质结构预测。利用MEGA 11采用邻接法(参数为:Poisson correction、Pairwise deletion、Bootstrap 1000)构建系统发育树[32,34-36]

1.2.6 转录组分析 以样品cDNA为模板、β-actin为内参基因(表 2),利用qRT-PCR验证转录组数据的可信性[35,37]。反应体系:cDNA 1.6 μL,引物β-actin-q-S和β-actin-q-A各0.8 μL,ddH2O 6.8 μL,2×T5 Fast qPCR Mix 10 μL。反应条件:95 ℃ 1 min;95 ℃ 10 s、56 ℃ 5 s、72 ℃ 10 s,40个循环;95 ℃ 5 s;65 ℃ 5 s;95 ℃ 20 s。

1.2.7 dfprl与其受体基因的原位杂交 实验室前期工作已克隆得到七彩神仙鱼催乳素受体基因dfprlr(数据库基因号:EVM0008977)。设计原位杂交探针,筛选出特异性高的探针并合成,样品经固定液处理后进行石蜡切片SweAMI探针原位杂交。

dfprl基因探针如下:

5'-CTGCCAAAAGGAGGGAAGTGAGAG-3'

5'-CGAGGTCAGTGCCTCCTCTGTAG-3'

5'-GAGGCAGGACAGCAGAAAATTGAA-3'

dfprlr基因探针如下:

5'-CTCTTTTTCAGGAGAACGGCATCG-3'

5'-GAGATACTCGGGAACTTTGATGTAGGAA-3'

5'-GATAGTACAGAGCGTAAGTAGTTGGCATT-3'

5'-GACCCAGATAACGGTGTTGTTCTTGT-3'

5'-GCTCATAGATTAGAGTGATCCAACCGG-3'

2 结果与分析 2.1 七彩神仙鱼dfprl基因的筛选、克隆及结构分析

为鉴定七彩神仙鱼基因组中的dfprl基因,采用17种硬骨鱼的PRL蛋白序列、Hormone_1结构域(PF00103)和PRL蛋白的特征基序作为依据,分别使用BLASTP算法对七彩神仙鱼基因组数据库进行搜索。结果筛选并鉴定出1个七彩神仙鱼PRL基因,命名为dfprl(数据库基因号:EVM0024940)。

dfprl的cDNA序列开放阅读框(ORF)长度为639 bp,共编码212个氨基酸,5'-UTR为309 bp,3'-UTR为334 bp,全长为1 282 bp(图 1)。

起始密码子(ATG)和终止密码子(TGA)标注为加粗红色字体,信号肽用阴影标出,Hormone_1结构域用直线标出 The initiation codon (ATG) and termination codon (TGA) are labeled with bold red font, the signal peptide is shaded and Hormone_1 domain is marked with a straight line 图 1 七彩神仙鱼dfprl全长序列及氨基酸序列 Fig. 1 Full-length sequence and amino acid sequence of dfprl of discus fish

dfprl基因ORF编码的氨基酸分子量为23.48 kD,等电点为9.13,亲水性总平均值(GRAVY)为-0.190,dfprl属于亲水性蛋白,分子式为C 1020H1677N295O310S14,脂肪指数为91.60,不稳定指数为52.79,dfprl为不稳定蛋白。dfprl的结构域主要由Hormone_1组成。对dfprl蛋白的二级结构进行预测,发现α-螺旋占整体的58.49%、β-转角占2.83%、延伸链占0.94%、无规则卷曲占37.74%(图 2)。对dfprl蛋白三级结构进行预测,结果表明其与尼加拉瓜湖始丽鱼AcPRL-1蛋白、人hPRL蛋白的相似度均较高,均达80% 以上。

蓝色:α-螺旋,绿色:β-转角,红色:延伸链,紫色:无规则卷曲 Blue: α-helix, green: β-turn, red: Extended strand, purple: random coil 图 2 七彩神仙鱼dfprl蛋白质二级结构 Fig. 2 Secondary structure of dfprl protein in discus fish

BLAST同源性对比结果显示,dfprl与17种鱼的PRL同源性较高,与尼加拉瓜湖始丽鱼同源性最高(96.70%),与其他16种鱼的同源性均大于80%。多序列比对结果(图 3)表明,PRL家族的Hormone_1结构域和部分特征基序在鱼类中高度保守。系统发育树结果表明高等动物PRL与鱼类PRL的进化距离相对较远,但整体进化距离差距不大。鱼类中,慈鲷科PRL聚为一簇,非慈鲷科鱼类聚为一簇,其中七彩神仙鱼dfprl和尼加拉瓜湖始丽鱼AcPRL-1聚在同一分支,进化关系最近(图 4)。

图 3 七彩神仙鱼dfprl与其他鱼类PRL的氨基酸序列比对 Fig. 3 Sequence alignment of PRL amino acids between dfprl of discus fish and other fish

图 4 七彩神仙鱼dfprl蛋白与其他物种PRL蛋白的系统发育树 Fig. 4 Phylogenetic tree analysis of dfprl and PRL proteins from other species

2.2 七彩神仙鱼dfprl基因的表达分析

转录组分析显示,dfprl基因在七彩神仙鱼亲本雌雄鱼中的表达略有差异。在整个抚育周期内,dfprl在亲鱼脑中的平均表达水平低于其在亲鱼性腺和皮肤中的表达水平(图 5)。在性腺中,雌雄七彩神仙鱼的表达趋势一致,在雄性精巢中的表达量较高。在精巢中,dfprl表达水平在NB期到S期之间下降,在S期、P1期和P7期逐步上升,NP期间又有所回降,NB期和NP期的表达量无显著差异。在皮肤中,雌雄七彩神仙鱼的表达趋势有明显差异,在S期雌鱼dfprl mRNA水平表达明显上调,在P1期、P7期和NP期逐渐下降;雄鱼进入抚育期后,dfprl mRNA水平逐渐上调,在NP期有所下降。

图 5 dfprl基因在七彩神仙鱼脑、性腺、皮肤中的表达模式 Fig. 5 Expression patterns of dfprl gene in brain, gonad and skin of discus fish

2.3 七彩神仙鱼dfprldfprlr基因的原位杂交

图 6可知,dfprl基因的荧光素标记为绿色,dfprlr基因的荧光素标记为红色,可见,dfprldfprlr基因在皮肤组织的粘液细胞中均有表达,且表达位点相近。dfprl在S期的荧光色最为明显,说明表达量较高;P1期、P7期和NP期荧光色逐渐变暗,说明表达量逐渐下降,这与转录组表达趋势相符。dfprldfprlr在P1期和P7期重叠明显。

a:细胞核荧光色,b:dfprlr基因荧光色,c:dfprl基因荧光色,d:全部荧光色 a: nuclear fluorescence, b: dfprlr gene fluorescence, c: dfprl gene fluorescence, d: full fluorescence 图 6 七彩神仙鱼S期、P1期、P7期和NP期皮肤原位杂交结果 Fig. 6 Paraffin-fluorescence probe-FISH result of skin in discus fish during S-stage, P1-stage, P7-stage and NP-stage

3 讨论

催乳素对哺乳动物、两栖动物、鸟类和鱼类的繁殖、内分泌、免疫等方面均起重要作用[14,16-23]。目前,在所有脊椎动物中均发现了PRL的同源基因[20,38-39]。本研究从七彩神仙鱼中克隆了dfprl基因全长,通过蛋白结构预测,发现七彩神仙鱼dfprl和人类hPRL、尼加拉瓜湖始丽鱼AcPRL-1蛋白的三级结构相似,表明PRL蛋白功能相近。已有研究表明,哺乳动物PRL蛋白的N端、中部和C端存在3个二硫键,但硬骨鱼PRL的N端缺乏12~14个氨基酸,导致其缺乏N端二硫键[17,40]。一项对鲑鱼(Oncorhynchus keta)的研究首次证明典型的哺乳动物PRL基因结构在鱼类中是保守的[41]。硬骨鱼类的PRL具有共同的保守结构域,并含有4个相对保守的半胱氨酸残基,其中1个半胱氨酸残基在C端。本研究中,七彩神仙鱼dfprl由212个氨基酸组成,也含有4个半胱氨酸残基,可能在成熟dfprl蛋白中形成2个二硫键,与其他硬骨鱼PRL结构一致。对七彩神仙鱼dfprl和其他物种的PRL蛋白进行多序列比对分析,结果发现所有PRL蛋白均含有保守的Hormone _1结构域及其侧翼。可见,dfprl在硬骨鱼中高度保守,与其他脊椎动物也具有共同的结构域[14,39,42-43]

研究表明,催乳素和催乳素受体在真兽类和后兽类的雌性和雄性大脑中均有表达,在雌性生殖器官和组织(如子宫、胎盘和乳腺)中表达明显增加[24,44]。在哺乳动物和鸟类中,催乳素已被证明在生殖发育(包括促进性成熟)中发挥作用,包括乳房生长和卵母细胞成熟(哺乳动物)和嗉囊生长(鸟类)[24-25,45-46]。PRL还调节各种生殖活动,影响激素受体丰度和性腺功能[17],在促进黄体存活和类固醇生成方面发挥重要作用[47]。虽然对鱼类催乳素的研究较少,但有证据表明催乳素在鱼类生殖活动中具有类似功能[14,18,48]

七彩神仙鱼亲鱼通过提供皮肤产生的粘液进行抚育,研究表明PRL信号可能在其粘液产生过程中发挥作用[4,31,49]。本研究对dfprl基因在七彩神仙鱼亲代抚育周期中的表达进行分析,结果表明,在亲鱼进入亲代抚育周期后,dfprl在性腺中的表达水平均上升,在雌鱼皮肤中表达水平明显上调,在雄鱼皮肤中表达水平上调略有滞后,但dfprl在亲鱼皮肤中整体表达上升,这与先前推测七彩神仙鱼催乳素调控亲代抚育期间粘液供养行为的观点一致。进一步通过对NB期、P1期、P7期和NP期皮肤组织进行原位杂交定位及半定量分析,结果显示,dfprldfprlr在皮肤粘液细胞中共表达,原位杂交表达与转录组表达趋势一致,在S期后dfprldfprlr的结合逐渐明显,表明在抚育期间dfprl很可能通过dfprlr进而在皮肤粘液细胞中起作用。本研究为了解鱼类亲代抚育行为并阐明dfprl基因在七彩神仙鱼亲鱼粘液供养行为中的作用及具体机制奠定基础,扩充了鱼类PRL功能的相关研究。

4 结论

本研究从七彩神仙鱼全基因组数据中筛选鉴定出1个PRL基因(dfprl)。对dfprl进行基因结构及蛋白结构等一系列比对分析,结果显示PRL在鱼类和高等动物中高度保守,一致性均大于80%,dfprl与PRL家族其他成员一致,均存在稳定的Hormone_1结构域。dfprl在精巢中的表达量明显较高,且进入产卵期后,dfprl在皮肤中的表达显著上调。在抚育阶段七彩神仙鱼亲代性腺和皮肤中dfprl高表达,表明dfprl可能参与亲代抚育行为的发生。原位杂交切片结果显示,dfprldfprlr在七彩神仙鱼亲代抚育阶段皮肤粘液细胞中的表达位点高度重合,暗示dfprl可能通过与dfprlr结合参与调控七彩神仙鱼皮肤分泌粘液,从而维持亲代抚育行为。

参考文献(References):
[1]
BUCKLEY J, MAUNDER R J, FOEY A, PEARCE J, VAL A L, SLOMAN K A. Biparental mucus feeding: Aunique example of parental care in an Amazonian cichlid[J]. Journal of Experimental Biology, 2010, 213(22): 3787-3795. DOI:10.1242/jeb.042929
[2]
SATOH S, TANOUE H, RUITTON S, MOHRI M, KOMATSU T. Morphological and behavioral ontogeny in larval and early juvenile discus fish Symphysodon aequifasciatus[J]. Ichthyological Research, 2016, 64(1): 37-44. DOI:10.1007/s10228-016-0530-y
[3]
SATOH S, TANOUE H, MOHRI M. Costs and benefits of biparental mucus provisioning in discus fish (Symphysodon aequifasciatus)[J]. Ichthyological Research, 2018, 65(4): 510-514. DOI:10.1007/s10228-018-0636-5
[4]
KHONG HK, KUAH MK, JAYA-RAM A, SHU-CHIEN A C. Prolactin receptor mRNA is upregulated in discus fish (Symphysodon aequifasciata) skin during parental phase[J]. Comparative Biochemistry and Physiology Part B: Biochemistry and Molecular Biology, 2009, 153(1): 18-28. DOI:10.1016/j.cbpb.2009.01.005
[5]
魏域玲, 温彬, 高建忠, 陈再忠. 七彩神仙鱼(Symphysodon haraldi) Otx2基因克隆及其表达分析[J]. 淡水渔业, 2021, 353(3): 13-19. DOI:10.3969/j.issn.1000-6907.2021.03.002
WEI Y L, WEN B, GAO J Z, CHEN Z Z. Otx2 gene cloning and expression analysis of Symphysodon haraldi[J]. Freshwater Fisheries, 2021, 353(3): 13-19. DOI:10.3969/j.issn.1000-6907.2021.03.002
[6]
BRIDGES R S. Neuroendocrine regulation of maternal behavior[J]. Frontiers in Neuroendocrinology, 2015, 36: 178-196. DOI:10.1016/j.yfrne.2014.11.007
[7]
STIVER K A, ALONZO S H. Parental and mating effort: Is there necessarily a trade-off?[J]. Ethology, 2009, 115(12): 1101-1126. DOI:10.1111/j.1439-0310.2009.01707.x
[8]
ZERA A J, HARSHMAN L G. The physiology of life history trade-offs in animals[J]. Annual Review of Ecology and Systematics, 2001, 32(1): 95-126. DOI:10.1146/annurev.ecolsys.32.081501.114006
[9]
KETTERSON E D, ATWELL J W, MCGLOTHLIN J W. Phenotypic integration and independence: Hormones, performance, and response to environmental change[J]. Integrative and Comparative Biology, 2009, 49(4): 365-379. DOI:10.1093/icb/icp057
[10]
SPECKER J L, KISHIDA M, HUANG L, KING D S, NAGAHAMA Y, UEDA H, ANDERSON T R. Immunocytochemical and immunogold localization of two prolactin isoforms in the same pituitary cells and in the same granules in the tilapia (Oreochromis mossambicus)[J]. General and Comparative Endocrinology, 1993, 89(1): 28-38. DOI:10.1006/gcen.1993.1006
[11]
OSCAR RIDDLE R W B, SIMON W D. The preparation, identification and assay of prolactin-a hormone of the anterior pituitary.[J]. American Journal of Physiology, 1993, 105: 191-216. DOI:10.1152/ajplegacy.1933.105.1.191
[12]
KUPFER A, MÜLLER H, ANTONIAZZI M M, JARED C, GREVEN H, NUSSBAUM R A, WILKINSON M. Parental investment by skin feeding in a caecilian amphibian[J]. Nature, 2006, 440(7086): 926-929. DOI:10.1038/nature04403
[13]
SATOH S, SOWERSBY W. Mucus provisioning behavior in teleost fishes: Anovel model system for the evolution of secretory provisioning in vertebrates[J]. Ichthyological Research, 2020, 68(1): 1-10. DOI:10.1007/s10228-020-00785-z
[14]
WHITTINGTON C M, WILSON A B. The role of prolactin in fish reproduction[J]. General and Comparative Endocrinology, 2013, 191: 123-136. DOI:10.1016/j.ygcen.2013.05.027
[15]
ANGELIER F, CHASTEL O. Stress, prolactin and parental investment in birds: A review[J]. General and Comparative Endocrinology, 2009, 163(1/2): 142-148. DOI:10.1016/j.ygcen.2009.03.028
[16]
BACHELOT A, BINART N. Reproductive role of prolactin[J]. Reproduction, 2007, 133(2): 361-369. DOI:10.1530/rep-06-0299
[17]
KELLY P A, BINART N, EDERY M, GOFFIN V, BOLE-FEYSOT C. Prolactin (prl) and its receptor: Actions, signal transduction pathways and phenotypes observed in prl receptor knockout mice[J]. Endocrine Reviews, 1998, 19(3): 225-268. DOI:10.1210/edrv.19.3.0334
[18]
SHU Y, LOU Q, DAI Z, DAI X, HE J, HU W, YIN Z. The basal function of teleost prolactin as a key regulator on ion uptake identified with zebrafish knockout models[J]. Scientific Reports, 2016, 6(1): 18597. DOI:10.1038/srep18597
[19]
BREVES J P, MCCORMICK S D, KARLSTROM R O. Prolactin and teleost ionocytes: New insights into cellular and molecular targets of prolactin in vertebrate epithelia[J]. General and Comparative Endocrinology, 2014, 203: 21-28. DOI:10.1016/j.ygcen.2013.12.014
[20]
FORSYTH I A, WALLIS M. Growth hormone and prolactin--molecular and functional evolution[J]. Journal of Mammary Gland Biology and Neoplasia, 2002, 7(3): 291-312. DOI:10.1023/a:1022804817104
[21]
HOAR W. Comparative physiology: Hormones and reproduction in fishes[J]. Annual Review of Physiology, 1965, 27(1): 51-70. DOI:10.1146/annurev.ph.27.030165.000411
[22]
SCHRADIN C, ANZENBERGER G. Prolactin, the hormone of paternity[J]. Physiology, 1999, 14(6): 223-231. DOI:10.1152/physiologyonline.1999.14.6.223
[23]
ZIEGLER T E. Hormones associated with non-maternal infant care: A review of mammalian and avian studies[J]. Folia Primatologica, 2000, 71(1/2): 6-21. DOI:10.1159/000021726
[24]
AUSTIN S H, KRAUSE J S, VIERNES R, FARRAR V S, BOOTH A M, HARRIS R M, ANGELIER F, LEE C, BOND A, WINGFIELD J C, MACMANES M M, CALISI R M. Uncovering the sex-specific endocrine responses to reproduction and parental care[J]. Frontiers in Endocrinology, 2021, 12: 1160. DOI:10.3389/fendo.2021.631384
[25]
FARRAR V S, HARRIS R M, AUSTIN S H, NAVA ULTRERAS B M, BOOTH A M, ANGELIER F, LANG A S, FEUSTEL T, LEE C, BOND A, MACMANES M D, CALISI R M. Prolactin and prolactin receptor expression in the hpg axis and crop during parental care in both sexes of a biparental bird (Columba livia)[J]. General and Comparative Endocrinology, 2022, 315: 113940. DOI:10.1016/j.ygcen.2021.113940
[26]
BLÜM V. Immunological determination of injected mammalian prolactin in cichlid fishes[J]. General and Comparative Endocrinology, 1968, 11(3): 595-602. DOI:10.1016/0016-6480(68)90075-0
[27]
MACHEMER L, FIEDLER K. Zur Hormonalen steuerung des schaumnestbaues beim paradiesfisch, Macropodus opercularis L. (Anabantidae, teleostei)[J]. Naturwissenschaften, 1965, 52: 648-649. DOI:10.1007/BF00637707
[28]
MACHEMER L. Synergistische Wirkung Von Säuger‐Prolaktin und androgen beim schaumnestbau des paradiesfisches, Macropodus opercularis L (Anabantidae)[J]. Zeitschrift fÜr Tierpsychologie, 1971, 28(1): 33-53. DOI:10.1111/j.1439-0310.1971.tb00588.x
[29]
DE RUITER A, BONGA S W, SLIJKHUIS H, BAGGERMAN B. The effect of prolactin on fanning behavior in the male three-spined stickleback, Gasterosteus aculeatus L.[J]. General and Comparative Endocrinology, 1986, 64(2): 273-283. DOI:10.1016/0016-6480(86)90014-6
[30]
KINDLER P M, BAHR J M, GROSS M R, PHILIPP D P. Hormonal regulation of parental care behavior in nesting male bluegills: Do the effects of bromocriptine suggest a role for prolactin?[J]. Physiological Zoology, 1991, 64(1): 310-322. DOI:10.1086/physzool.64.1.30158526
[31]
BLüM V, FIEDLER K. Hormonal control of reproductive behavior in some cichlid fish[J]. General and Comparative Endocrinology, 1965, 5(2): 186-196. DOI:10.1016/0016-6480(65)90113-9
[32]
王片片, 康桦华, 刘振兴, 王芳, 刘春. 剑尾鱼IgD基因的克隆及其在嗜水气单胞菌疫苗免疫后的表达变化[J]. 广东农业科学, 2022, 49(2): 143-150. DOI:10.16768/j.issn.1004-874X.2022.02.017
WANG P P, KANG H H, LIU Z X, WANG F, LIU C. Cloning of IgD gene in swordtail fish and changes of its responses to aeromonas hydrophila vaccine challenges[J]. Guangdong Agricultural Sciences, 2022, 49(2): 143-150. DOI:10.16768/j.issn.1004-874X.2022.02.017
[33]
屈子啸, 杨帅朋, 朱向星, 唐冬生. 基于全基因组重测序挖掘大白-长白二元母猪产仔数性状候选基因[J]. 广东农业科学, 2023, 50(3): 120-128. DOI:10.16768/j.issn.1004-874X.2023.03.014
QU Z X, YANG S P, ZHU X X, TANG D S. Mining candidate genes for litter size traits in large white-landrace crossbred sows based on whole genome resequencing[J]. Guangdong Agricultural Sciences, 2023, 50(3): 120-128. DOI:10.16768/j.issn.1004-874X.2023.03.014
[34]
刘鑫, 温彬, 马腾飞, 缪琳, 高建忠, 陈再忠. 七彩神仙鱼免疫球蛋白超家族成员jam-Acd22基因克隆及表达分析[J]. 淡水渔业, 2022, 362(6): 58-66. DOI:10.13721/j.cnki.dsyy.2022.06.012
LIU X, WEN B, MA T F, MIAO L, GAO J Z, CHEN Z Z. Molecular cloning and expression analysis of immunoglobulin superfamily members jam-A and cd22 in Symphysodon aequifasciatus[J]. Freshwater Fisheries, 2022, 362(6): 58-66. DOI:10.13721/j.cnki.dsyy.2022.06.012
[35]
LIU X, DING X F, WEN B, MA T F, QIN W, LI Z J, ZHANG Y S, GAO J Z, CHEN Z Z. Genome-wide identification and skin expression of immunoglobulin superfamily in discus fish (Symphysodon Aequifasciatus) reveal common genes associated with vertebrate lactation[J]. Gene, 2023, 862: 147260. DOI:10.1016/j.gene.2023.147260
[36]
TAMURA K, STECHER G, KUMAR S, BATTISTUZZI F U. Mega11: Molecular evolutionary genetics analysis version 11[J]. Molecular Biology and Evolution, 2021, 38(7): 3022-3027. DOI:10.1093/molbev/msab120
[37]
张婷婷, 谭永强, 刘莹, 袁改改, 芮荣涛, 周扬, 凌冬. 盐胁迫下转DCCIPK24拟南芥的转录组比较分析[J]. 广东农业科学, 2023, 50(10): 75-84. DOI:10.16768/j.issn.1004-874X.2023.10.009
ZHANG T T, TAN Y Q, LIU Y, YUAN G G, RUI R T, ZHOU Y, LING D. Comparative transcriptome analysis of DcCIPK24 transgenic Arabidopsis under salt stress[J]. Guangdong Agricultural Sciences, 2023, 50(10): 75-84. DOI:10.16768/j.issn.1004-874X.2023.10.009
[38]
POWER D M. Developmental ontogeny of prolactin and its receptor in fish[J]. General and Comparative Endocrinology, 2005, 142(1/2): 25-33. DOI:10.1016/j.ygcen.2004.10.003
[39]
LI Y, ZHANG Y P. Molecular evolution of prolactin gene family in rodents[J]. Acta Genetica Sinica, 2006, 33(7): 590-597. DOI:10.1016/s0379-4172(6)60088-7
[40]
RAND-WEAVER M. Evolution of the structure of the growth hormone and prolaction family[J/OL]. The Endocrinology of Growth, Development and Metabolism in Vertebrates, 1993: 13-42. https://cir.nii.ac.jp/crid/1570572699892009984.
[41]
HIROSHI K, AKIYOSHI T, TETSUYA H, SANAE H, NOBUKO N, YASUMITSU N. Isolation and properties of chum salmon prolactin[J]. General and Comparative Endocrinology, 1983, 49: 446-458. DOI:10.1016/0016-6480(83)90208-3
[42]
CUNHA A A P, PARTRIDGE C G, KNAPP R, NEFF B D. Androgen and prolactin manipulation induces changes in aggressive and nurturing behavior in a fish with male parental care[J]. Hormones and Behavior, 2019, 116: 104582. DOI:10.1016/j.yhbeh.2019.104582
[43]
YANG M, YANG M, LIN Y, MENG F, DU X, ZENG X, BU G. Characterization of prolactin (prl) and prl receptor (prlr) in Chinese soft-shelled turtle: Molecular identification, ligand-receptor interaction and tissue distribution[J]. General and Comparative Endocrinology, 2022, 316: 113941. DOI:10.1016/j.ygcen.2021.113941
[44]
AOKI M, WARTENBERG P, GRüNEWALD R, PHILLIPPS H R, WYATT A, GRATTAN D R, BOEHM U. Widespread cell-specific prolactin receptor expression in multiple murine organs[J]. Endocrinology, 2019, 160(11): 2587-2599. DOI:10.1210/en.2019-00234
[45]
SWART J M, GRATTAN D R, LADYMAN S R, BROWN R S E. Changes in maternal motivation across reproductive states in mice: a role for prolactin receptor activation on gaba neurons[J]. Hormones and Behavior, 2021, 135: 105041. DOI:10.1016/j.yhbeh.2021.105041
[46]
PARé P, REALES G, PAIXãO-CôRTES V R, VARGAS-PINILLA P, VISCARDI L H, FAM B, PISSINATTI A, SANTOS F R, BORTOLINI M C. Molecular evolutionary insights from prlr in mammals[J]. General and Comparative Endocrinology, 2021, 309: 113791. DOI:10.1016/j.ygcen.2021.113791
[47]
BOUILLY J, SONIGO C, AUFFRET J, GIBORI G, BINART N. Prolactin signaling mechanisms in ovary[J]. Molecular and Cellular Endocrinology, 2012, 356(1/2): 80-87. DOI:10.1016/j.mce.2011.05.004
[48]
SEALE A P, GRAU E G, LERNER D T, MORIYAMA S, YAMAGUCHI Y. Autocrine positive feedback regulation of prolactin release from tilapia prolactin cells and its modulation by extracellular osmolality[J]. Endocrinolog y, 2016, 157(9): 3505-3516. DOI:10.1210/en.2015-1969
[49]
WEN B, ZHOU J Q, GAO J Z, CHEN H R, SHEN Y Q, CHEN Z Z. Sex-dependent changes in the skin mucus metabolome of discus fish (Symphysodon haraldi) during biparental care[J]. Journal of Proteomics, 2020, 221: 103784. DOI:10.1016/j.jprot.2020.103784

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