Zhang Xiaoyan, Hou Jilun, Wang Guixing, Jiang Hongbo, Wang Yufen, Sun Zhaohui, Jiang Xiufeng, Yu Qinghai, Liu Haijin
Beidaihe Central Experiment Station, Chinese Academy of Fishery Sciences, Qinhuangdao, China.
College of Animal Science and Veterinary Medicine, Shenyang Agricultural University, Shenyang, China.
PLoS One. 2015 Nov 18;10(11):e0143204. doi: 10.1371/journal.pone.0143204. eCollection 2015.
Sterility is a serious problem that can affect all bionts. In teleosts, double haploids (DHs) induced by mitogynogenesis are often sterile. This sterility severely restricts the further application of DHs for production of clones, genetic analysis, and breeding. However, sterile DH individuals are good source materials for investigation of the molecular mechanisms of gonad development, especially for studies into the role of genes that are indispensable for fish reproduction. Here, we used the Illumina sequencing platform to analyze the transcriptome of sterile female DH Japanese flounder in order to identify major genes that cause sterility and to provide a molecular basis for an intensive study of gonadal development in teleosts. Through sequencing, assembly, and annotation, we obtained 52,474 contigs and found that 60.7% of these shared homologies with existing sequences. A total of 1225 differentially expressed unigenes were found, including 492 upregulated and 733 downregulated genes. Gene Ontology and KEGG analyses showed that genes showing significant upregulation, such as CYP11A1, CYP11B2, CYP17, CYP21, HSD3β, bcl2l1, and PRLR, principally correlated with sterol metabolic process, steroid biosynthetic process, and the Jak-stat signaling pathway. The significantly downregulated genes were primarily associated with immune response, antigen processing and presentation, cytokine-cytokine receptor interaction, and protein digestion and absorption. Using a co-expression network analysis, we conducted a comprehensive comparison of gene expression in the gonads of fertile and sterile female DH Japanese flounder. Identification of genes showing significantly different expression will provide further insights into DH reproductive dysfunction and oocyte maturation processes in teleosts.
不育是一个会影响所有生物的严重问题。在硬骨鱼类中，通过雌核发育诱导产生的双单倍体（DHs）通常是不育的。这种不育严重限制了双单倍体在克隆生产、遗传分析和育种方面的进一步应用。然而，不育的双单倍体个体是研究性腺发育分子机制的良好材料来源，特别是对于研究鱼类繁殖中不可或缺的基因的作用。在此，我们使用Illumina测序平台分析不育雌性双单倍体牙鲆的转录组，以鉴定导致不育的主要基因，并为深入研究硬骨鱼类性腺发育提供分子基础。通过测序、组装和注释，我们获得了52474个重叠群，发现其中60.7%与现有序列具有同源性。共发现1225个差异表达的单基因，包括492个上调基因和733个下调基因。基因本体论和KEGG分析表明，显著上调的基因，如CYP11A1、CYP11B2、CYP17、CYP21、HSD3β、bcl2l1和PRLR，主要与甾醇代谢过程、类固醇生物合成过程以及Jak - stat信号通路相关。显著下调的基因主要与免疫反应、抗原加工和呈递、细胞因子 - 细胞因子受体相互作用以及蛋白质消化和吸收相关。通过共表达网络分析，我们对可育和不育雌性双单倍体牙鲆性腺中的基因表达进行了全面比较。鉴定出表达有显著差异的基因将为深入了解硬骨鱼类双单倍体的生殖功能障碍和卵母细胞成熟过程提供进一步的见解。
