Zhang Zhilin, Yao Mingshuai, Zhu Guanyu, Chen Yong, Chen Ying, Sun Fuzhen, Zhang Yiling, Wang Qiang, Shen Zhongyuan
Jiangsu University of Science and Technology, Zhenjiang 212018, Jiangsu Province, China.
Jiangsu University of Science and Technology, Zhenjiang 212018, Jiangsu Province, China; Sericultural Research Institute, Chinese Academy of Agricultural Sciences, Zhenjiang 212018, Jiangsu Province, China.
J Invertebr Pathol. 2020 Jul;174:107441. doi: 10.1016/j.jip.2020.107441. Epub 2020 Jul 11.
Splicing factors are important components of RNA editing in eukaryotic organisms and can produce many functional and coding genes, which is an indispensable step for the correct expression of corresponding proteins. In this study, we identified splicing factor arginine/serine-rich 10 protein in the microsporidian Nosema bombycis and named it NbSRSF10. The NbSRSF10 gene contains a complete ORF of 1449 bp in length that encodes a 482-amino acid polypeptide. The isoelectric point (pI) of the protein encoded by NbSRSF10 gene was 4.94. NbSRSF10 has a molecular weight of 54.6 k and has no signal peptide. NbSRSF10 is comprised of arginine (11.41%), glutamic acid (11.41%) and serine (9.54%) among the total amino acids, and 7 α-helix, 7 β-sheet and 15 random coils in secondary structure, and contains 71 phosphorylation sites, 22 N-glycosylation sites and 20 O-glycosylation sites. The three-dimensional structure of NbSRSF10 is similar to that of transformer-2 beta of Homo sapiens (hTra2-β). Indirect immunofluorescence showed that the NbSRSF10 is localized in the cytoplasm of the dormant microsporidian spore and is transferred to the nuclei when N. bombycis develops into the proliferative and sporogonic phase. qPCR revealed that the relative expression of NbSRSF10 increased in the meronts stage and was found at a relatively low level in the sporogonic phase of development of N. bombycis, and was up-regulated again during infection in the host cell and early proliferative phase of second life cycle. These results suggested that the NbSRSF10 may participate in the whole life cycle and play an important role in transcription regulation of N. bombycis.
剪接因子是真核生物中RNA编辑的重要组成部分，可产生许多功能性和编码基因，这是相应蛋白质正确表达不可或缺的一步。在本研究中，我们在微孢子虫家蚕微孢子虫中鉴定出富含精氨酸/丝氨酸的剪接因子10蛋白，并将其命名为NbSRSF10。NbSRSF10基因包含一个长度为1449 bp的完整开放阅读框，编码一个482个氨基酸的多肽。NbSRSF10基因编码的蛋白质的等电点（pI）为4.94。NbSRSF10的分子量为54.6 k，没有信号肽。NbSRSF10在总氨基酸中由精氨酸（11.41%）、谷氨酸（11.41%）和丝氨酸（9.54%）组成，二级结构中有7个α螺旋、7个β折叠和15个无规卷曲，包含71个磷酸化位点、22个N-糖基化位点和20个O-糖基化位点。NbSRSF10的三维结构与智人的transformer-2 beta（hTra2-β）相似。间接免疫荧光显示，NbSRSF10定位于休眠微孢子虫孢子的细胞质中，当家蚕微孢子虫发育到增殖和孢子生殖阶段时转移到细胞核中。qPCR显示，NbSRSF10的相对表达在裂殖体阶段增加，在家蚕微孢子虫发育的孢子生殖阶段处于相对较低水平，在宿主细胞感染和第二个生命周期的早期增殖阶段再次上调。这些结果表明，NbSRSF10可能参与整个生命周期，并在家蚕微孢子虫的转录调控中发挥重要作用。
