Magnadóttir Bergljót, Bragason Birkir Thor, Bricknell Ian R, Bowden Timothy, Nicholas Anthony P, Hristova Mariya, Guðmundsdóttir Sigríður, Dodds Alister W, Lange Sigrun
Institute for Experimental Pathology, University of Iceland, Keldur v. Vesturlandsveg, 112 Reykjavik, Iceland.
Aquaculture Research Institute School of Marine Sciences, University of Maine, Orono, ME, USA.
Dev Comp Immunol. 2019 Mar;92:1-19. doi: 10.1016/j.dci.2018.10.016. Epub 2018 Nov 3.
Post-translational protein deimination is mediated by peptidylarginine deiminases (PADs), which are calcium dependent enzymes conserved throughout phylogeny with physiological and pathophysiological roles. Protein deimination occurs via the conversion of protein arginine into citrulline, leading to structural and functional changes in target proteins. In a continuous series of early halibut development from 37 to 1050° d, PAD, total deiminated proteins and deiminated histone H3 showed variation in temporal and spatial detection in various organs including yolksac, muscle, skin, liver, brain, eye, spinal cord, chondrocytes, heart, intestines, kidney and pancreas throughout early ontogeny. For the first time in any species, deimination of complement components C3 and C4 is shown in halibut serum, indicating a novel mechanism of complement regulation in immune responses and homeostasis. Proteomic analysis of deiminated target proteins in halibut serum further identified complement components C5, C7, C8 C9 and C1 inhibitor, as well as various other immunogenic, metabolic, cytoskeletal and nuclear proteins. Post-translational deimination may facilitate protein moonlighting, an evolutionary conserved phenomenon, allowing one polypeptide chain to carry out various functions to meet functional requirements for diverse roles in immune defences and tissue remodelling.
翻译后蛋白质脱亚氨基作用由肽基精氨酸脱亚氨酶（PADs）介导，PADs是一类钙依赖性酶，在整个系统发育过程中保守，具有生理和病理生理作用。蛋白质脱亚氨基作用通过蛋白质精氨酸转化为瓜氨酸而发生，导致靶蛋白的结构和功能发生变化。在从37到1050度日的大比目鱼早期连续发育过程中，PAD、总脱亚氨基蛋白质和脱亚氨基组蛋白H3在包括卵黄囊、肌肉、皮肤、肝脏、大脑、眼睛、脊髓、软骨细胞、心脏、肠道、肾脏和胰腺在内的各种器官的早期个体发育过程中，在时间和空间检测上表现出差异。在任何物种中首次发现，大比目鱼血清中补体成分C3和C4发生脱亚氨基作用，这表明在免疫反应和体内平衡中补体调节存在一种新机制。对大比目鱼血清中脱亚氨基靶蛋白的蛋白质组学分析进一步鉴定出补体成分C5、C7、C8、C9和C1抑制剂，以及各种其他免疫原性、代谢、细胞骨架和核蛋白。翻译后脱亚氨基作用可能促进蛋白质兼职，这是一种进化保守现象，允许一条多肽链执行各种功能，以满足免疫防御和组织重塑中不同角色的功能需求。
