Functional analysis of small RNAs in pearl oyster, Pinctada fucata

在东京大学攻读博士学位期间，我对合浦珠母贝的小RNA种类、表达及其功能分析进行了研究，具体包括：（1）miRNAs的分类、鉴定、表达和靶点预测;（2）皮尔纳在体细胞和性腺组织中的鉴定、表达和生物发生分析。共鉴定出228个miRNAs，其中已知186个，新发现42个。此外，还利用珠母贝属105个生物矿化相关基因的全序列进行miRNAs靶标预测。在皮尔纳分析中，我们首次发现piRNA在合浦珠母贝的体细胞和性腺组织中广泛表达。证明了piRNA的表达模式和特征，这揭示了P. fucata生物学的一个令人着迷和意想不到的维度。使用转录组学分析鉴定了岩藻中的关键皮尔纳生物合成因子，包括PIWI、AGO、小西葫芦和HEN。我们还利用锁核酸修饰的寡核苷酸（locked-nucleic-acid modified oligonucleotide，LNA）敲除了表达量最高的piRNA 0001，以研究其在褐藻中的功能。小RNA的鉴定和鉴定将有助于进一步了解小RNA的生物合成机制和功能。总之，在此期间，我在高索引期刊上发表了6篇论文（4篇为第一作者，2篇为合著者），并在第14届国际生物矿化研讨会（2017年），JSFS（2017年，2018年和2019年），国际水生宏基因组学研讨会上发表了研究工作。

During the doctoral studying in the University of Tokyo, I do research about the small RNA species, expression, and their functional analysis in Pinctada fucata, more specifically on (1) classification, identification, expression and target prediction of miRNAs, and (2) piRNA identification, expression and biogenesis analysis in the somatic and gonad tissues. A total of 228 miRNAs, including 186 known and 42 novel miRNAs, were identified in P. fucata. Furthermore, 105 biomineralization-related genes with complete sequences from Pinctada genus were used for miRNAs target prediction. In piRNA analysis, we firstly found that piRNAs were ubiquitously expressed in somatic and gonad tissues in P. fucata. The expression patterns and characteristics of piRNAs were demonstrated, which reveal a fascinating and unanticipated dimension of P. fucata biology. The key piRNA biogenesis factors in P. fucata, including PIWI, AGO, Zucchini and HEN, were identified using transcriptomic analysis. We also knockdown the highest expressed piRNA0001 by locked-nucleic-acid modified oligonucleotide (LNA) to research its function in P. fucata. The characterization and identification of small RNAs will help to further understand the mechanism of small RNA biogenesis and its function in P. fucata. In summary, during this period I published 6 papers (4 as first authors and 2 as co-authors) in high-indexed journals, and presented the research work at 14th International Symposium on Biomineralization (2017), JSFS (2017, 2018 and 2019), International Symposium on Aquatic Metagenomics.