Functional analysis of small RNAs in pearl oyster, Pinctada fucata

在东京大学攻读博士学位期间，我对珠母贝小RNA的种类、表达及其功能分析进行了研究，特别是在(1)miRNAs的分类、鉴定、表达和靶标预测方面；(2)在体细胞和性腺组织中的piRNA鉴定、表达和生物发生分析。共鉴定出228个miRNAs，其中186个为已知miRNAs，42个为新的miRNAs。此外，还利用珠母贝属105个具有完整序列的生物矿化相关基因进行miRNAs靶标预测。在piRNA分析中，我们首次发现piRNAs在岩藻的体细胞和性腺组织中普遍表达。展示了piRNAs的表达模式和特征，揭示了岩藻生物学的一个令人着迷的和意想不到的维度。通过转录转录分析，确定了岩藻中关键的piRNA生物发生因子，包括PIWI、AGO、西葫芦和母鸡。我们还用锁定核酸修饰的寡核苷酸(LNA)敲除了最高表达的piRNA0001，以研究其在岩藻中的功能。对小RNA的鉴定和鉴定将有助于进一步了解小RNA在岩藻中的生物发生机制及其功能。总之，在此期间，我在高收录期刊上发表了6篇论文(4篇为第一作者，2篇为合著者)，并在第14届生物矿化国际研讨会(2017)、JSFs(2017、2018和2019年)、国际水产元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.