日本文昌鱼雄性高表达miRNA的筛选与鉴定

Screening and identification of highly expressed miRNAs in amphioxus Branchiostoma japonicum testis tissues

MicroRNA(miRNA)是真核生物中长度约为22个核苷酸的非编码小分子RNA,在基因表达调控中扮演重要角色。雌雄差异miRNA的筛选将有助于研究性腺发育的分子机制。通过分离日本文昌鱼(Branchiostoma japonicum)精巢和卵巢的小RNA,利用miRNA芯片杂交的方法,从文昌鱼的小RNA文库中筛选出36个日本文昌鱼性腺高表达的miRNA,其中11个miRNA在文昌鱼精卵巢中呈显著差异表达。6个文昌鱼特有的miRNA(bfl-miR-92b,bfl-miR-10A06,bfl-miR-281,bfl-miR-36B03,bfl-miR-29B02和bfl-miR-26A01)在雌雄性腺中呈现差异表达,其中4个miRNA为雄性高表达,2个miRNA为雌性高表达。利用RT-qPCR验证了bfl-miR-92b,bfl-miR-10A06,bfl-miR-281和bfl-miR-36B03这4个文昌鱼特有的miRNA在精巢中的丰富表达。这些研究结果为文昌鱼雌雄差异miRNA的功能研究奠定了重要基础。

MicroRNAs（miRNAs） are endogenous-22 nucleotide small non-coding RNAs in eukaryotes genomes,which play a very important role in gene expression regulation.Sexual dimorphism miRNA screening would help in understanding gonad development mechanism.In this study,we firstly isolated small RNAs from amphioxus Branchiostoma japonicum gonad.By microarray analysis,we totally identified 36 miRNAs,which were abundantly expressed in amphioxus gonad.Among them,11 miRNAs were regarded as sexual dimorphism miRNAs in amphioxus.Six miRNAs（bfl-miR-92b,bfl-miR-10A06,bfl-miR-281,bfl-miR-36B03,bfl-miR-29B02 and bfl-miR-26A01）specific to amphioxus were regarded as sexual dimorphism miRNAs,among which,4 miRNAs showed high expressions in testis whereas 2 miRNAs exhibited high expressions in ovary tissue.In addition,bfi-miR-92b,bfl-miR-10A06,bfl-miR-281 and bfl-miR-36B03 were identified as high abundantly expressed miRNA in amphioxus testis by using RT-qPCR techniques.All these results provided a basis for sexual dimorphism miRNA function identifications in the future.