近期，課題組科研人員對(duì)中華鱘原始生殖細(xì)胞的遷移和配子發(fā)生至關(guān)重要的基因dnd進(jìn)行了分離鑒定，并對(duì)其編碼氨基酸結(jié)構(gòu)及其在中華鱘生殖細(xì)胞中的表達(dá)進(jìn)行了研究。研究論文在國(guó)際知名雜志《Gene》上發(fā)表。

Abstract：Dead end (dnd) encodes an RNA-binding protein that is essential for primordial germ cell (PGC) migration and gametogenesis in vertebrates. In this study, a Chinese sturgeon Acipenser sinensis dead end homologue, designated

Asdnd,was identified and characterized. The full-length cDNA of Asdndwas 1630 base pairs (bp) and encoded a peptide of 396 amino acid residues.Multiple sequence alignment showed that AsDnd shared six conserved regions of Dnd orthologs, including the RNA recognition motif. Phylogenetic analysis revealed that AsDnd was grouped with teleosts. By quantitative real-time PCR analysis, the Asdnd transcripts were found to originate from the maternal parent and be specifically expressed in gonads of immature Chinese sturgeons of both sexes. Fluorescent in situ hybridization indicated that Asdnd transcriptswere restricted to germcells. In the testis, Asdnd was abundant in spermatogonia and tended to gradually diminish in late spermatogenic stages, while strong signals were found in primary oocytes, as opposed to oogonia, in the ovary. Zebrafish PGCs were clearly visualized at 24 h post-fertilization by co-injecting RFP-Asdnd 3′ UTR and GFP-nos3 3′ UTR mRNA, indicating that dnd 3′ UTR has a conserved function among teleosts. Therefore, dnd could serve as a germcellmarker in Chinese sturgeon.

摘要翻譯：Dead end（dnd）編碼一種RNA結(jié)合蛋白，對(duì)脊椎動(dòng)物原始生殖細(xì)胞的遷移和配子發(fā)生至關(guān)重要。在本研究中，分離鑒定了中華鱘（Acipenser sinensis）dead end的同源基因，即Asdnd。中華鱘dnd基因全長(zhǎng)cDNA序列為1630 bp，編碼396個(gè)氨基酸。通過氨基酸序列多重對(duì)比發(fā)現(xiàn)AsDnd與其他物種Dnd一樣，具有包括RNA識(shí)別域在內(nèi)的6個(gè)保守結(jié)構(gòu)域。進(jìn)化分析表明，中華鱘Dnd屬于硬骨魚類分支。qRT-PCR結(jié)果顯示，Asdnd mRNA為母系遺傳且僅在性腺組織中有表達(dá)。熒光原位雜交研究發(fā)現(xiàn)，Asdnd在生殖細(xì)胞中特異表達(dá)。在精巢中，Asdnd mRNA在精原細(xì)胞中表達(dá)最強(qiáng)，在后續(xù)的精子發(fā)生時(shí)期逐步減弱；在卵巢中，Asdnd mRNA在初級(jí)卵母細(xì)胞的表達(dá)較卵原細(xì)胞強(qiáng)。此外，通過顯微共注射RFP-Asdnd 3′ UTR和GFP-nos3 3′ UTR mRNA，斑馬魚的原始生殖細(xì)胞（PGCs）能被成功標(biāo)記，這表明dnd 3′ UTR在硬骨魚中可能具有保守功能。因此，dnd 可以作為中華鱘生殖細(xì)胞的標(biāo)記基因。