Huang Lin, Chen Shan Nan, Gan Zhen, Nie Pin
State Key Laboratory of Freshwater Ecology and Biotechnology, Key Laboratory of Aquaculture Disease Control, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, Hubei Province, 430072, China; University of Chinese Academy of Sciences, Beijing, 100049, China.
State Key Laboratory of Freshwater Ecology and Biotechnology, Key Laboratory of Aquaculture Disease Control, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, Hubei Province, 430072, China.
Dev Comp Immunol. 2021 Apr;117:103965. doi: 10.1016/j.dci.2020.103965. Epub 2020 Dec 10.
Peptidoglycan recognition proteins (PGRPs), which are discovered in invertebrates and vertebrates, play an important role in antibacterial immunity. However, the function of PGRPs is largely uninvestigated in reptiles. In the present study, a short-type PGRP gene, designed as C-turtle-PGRP-S, was identified in the Chinese soft-shelled turtle, Pelodiscus sinensis. The C-turtle-PGRP-S contains a highly conserved PGRP domain and has close relationship with PGRP-S orthologues in other species according to sequence and phylogenetic analyses. C-turtle-PGRP-S gene was constitutively expressed in all detected tissues and was induced by Edwardsiella tarda. Additionally, recombinant C-turtle-PGRP-S showed PGN binding activity and antibacterial function against E. tarda. Therefore, it is suggested that the function of PGRP-S is likely to be conserved in reptile vertebrates, as observed in other vertebrates, shedding light on the evolutionary conservation of PGRPs.
肽聚糖识别蛋白（PGRPs）在无脊椎动物和脊椎动物中均有发现，在抗菌免疫中发挥重要作用。然而，PGRPs在爬行动物中的功能在很大程度上尚未得到研究。在本研究中，在中国软壳龟（中华鳖）中鉴定出一个短型PGRP基因，命名为C-龟-PGRP-S。根据序列和系统发育分析，C-龟-PGRP-S包含一个高度保守的PGRP结构域，并且与其他物种中的PGRP-S直系同源物关系密切。C-龟-PGRP-S基因在所有检测的组织中组成性表达，并受到迟缓爱德华氏菌的诱导。此外，重组C-龟-PGRP-S表现出对肽聚糖的结合活性以及对迟缓爱德华氏菌的抗菌功能。因此，正如在其他脊椎动物中观察到的那样，提示PGRP-S的功能在爬行动物中可能是保守的，这为PGRPs的进化保守性提供了线索。
