鲂鲌杂交鱼染色体减数分裂特征及相关基因分析  

Analysis of the Characteristics of Meiotic Chromosomes and Related Genes in Hybrid Fish Derived from Megalobrama amblycephala×Culter alburnus

作　　者：汤陈宸 吴昌 李健[1,2] 陈乾 陶敏 张纯[1,2] 覃钦博 罗凯坤[1,2] 刘少军 TANG Chen-chen;WU Chang;LI Jian;CHEN Qian;TAO Min;ZHANG Chun;QIN Qin-bo;LUO Kai-kun;LIU Shao-jun(State Key Laboratory of Developmental Biology of Freshwater Fish,Hunan Normal University,Changsha 410081,Hunan,China;Engineering Research Center of Polyploid Fish Reproduction and Breeding of the State Education Ministry,College of Life Sciences,Hunan Normal University,Changsha 410081,Hunan,China)

机构地区：[1]湖南师范大学省部共建淡水鱼类发育生物学国家重点实验室,湖南长沙410081 [2]湖南师范大学生命科学学院多倍体鱼繁殖与育种技术教育部工程研究中心,湖南长沙410081

出　　处：《生命科学研究》2021年第4期303-309,326,共8页Life Science Research

基　　金：国家自然科学基金资助项目(U19A2040,31730098);财政部和农业农村部:国家现代农业产业技术体系资助(CARS-45);111计划项目(D20007);湖湘高层次人才聚集工程项目(2019RS1044);湖南省重点研发计划项目(2020NK2016)。

摘　　要：突破种间生殖难关,建立可育品系,在远缘杂交的遗传理论的创新和遗传育种方面都具有重要意义。本课题组利用团头鲂(Megalobrama amblycephala,BSB,2n=48,♀)与翘嘴鲌(Culter alburnus,TC,2n=48,♂)进行属间杂交,突破了鱼类远缘杂交生殖障碍,建立了鲂鲌杂交品系(BTF1-BTF6),为探究鱼类远缘杂交的遗传和繁殖规律提供了宝贵材料。本文在前期育种研究的基础上对鲂鲌杂交鱼减数分裂过程中生殖细胞染色体配对特征、减数分裂相关基因的序列和表达等开展了一系列研究。研究结果显示:鲂鲌F1精巢中的异源染色体能进行正常的联会配对,产生染色体数目减半的次级精母细胞;Dmc1和Rec8是与减数分裂相关的两个基因,其序列在团头鲂和翘嘴鲌中的相似性较高,但在杂交子代呈现偏母本遗传,且出现了不同程度嵌合现象;在鲂鲌F1精巢中,Dmc1基因的表达水平与其亲本相比无显著性差异(P<0.05),而Rec8基因的表达水平则介于亲本之间。这些结果为具有异源基因组的远缘杂交鱼能顺利进行减数分裂提供了重要的生物学证据。本研究在鱼类遗传育种研究方面具有重要意义。Breaking the reproduction barrier to produce fertile hybrid strains in distant hybridization of fish are of great significance in the innovation of genetic theory and genetic breeding.Intergeneric hybridization of Megalobrama amblycephala(BSB,2n=48,♀)and Culter alburnus(TC,2n=48,♂)was successfully per-formed and a hybrid lineage(BTF1-BTF6)was established,which breaks through the reproductive barriers of hybridization and provides a valuable material for studying the genetic and reproductive rules of distant hy-bridization in fish.Based on the previous studies on fish breeding,chromosome pairing of germ cells,meiosis-related gene expression,and gene sequences were analyzed in the present study.The results showed that the heterologous chromosomes derived from M.amblycephala and C.alburnus could make normal meiotic pairing and secondary spermatocytes could be produced with halved chromosomal number in BTF1 testes.Dmc1 and Rec8 are important genes related to meiosis,which had a high homology between M.amblycephala and C.alburnus,and showed partial maternal inheritance in BTF1 and different degrees of gene chimerism.In addi-tion,the expression level of Dmc1 gene in BTF1 testes was not significantly different from those of its parents(P<0.05),while the expression level of Rec8 gene was between those of its parents.These results provide an important insight for studying related mechanisms of normal meiosis in hybrid fish under the regulation of heterologous genome,and are of great value in fish genetics and breeding.

关 键 词：远缘杂交 杂交品系 减数分裂 染色体联会 Dmc1基因 Rec8基因 

分 类 号：Q321.8[生物学—遗传学] S917.4[农业科学—水产科学]