V型胶原蛋白被认为是鱼皮中至关重要的次要胶原蛋白,具有独特的生理功能。在这项研究中,从short鱼(Tetrapturusangustirostris)的皮肤中克隆了V型胶原蛋白中的三个原蛋白质(Tacol5a1,Tacol5a2和Tacol5a3)的cDNA。Tacol5a1,Tacol5a2和Tacol5a3的开放阅读框(ORF)包含5991、4485和5607bps,分别,编码1997、1495和1869个氨基酸残基。每个推导的前胶原的氨基酸序列都包含信号肽和纤维状胶原蛋白C末端结构域(COLFI)。在Tacol5a1和5a3原荧光体的N末端发现了保守的血小板反应蛋白样N末端结构域(TSPN),而在Tacol5a2前胶原的N末端发现了血管性血友病因子(VWC)。Tacol5a1,Tacol5a2和Tacol5a3的理论等电点分别为5.06,6.75和5.76,预测分子量分别为198,435.60,145,058.48和189,171.18。系统发育树分析显示,短嘴spear鱼的Tacol5a1与黄色鲈鱼(Percasavescens)聚集在一起,而不是宽嘴箭鱼(Xiphiasgladius)。此外,V型胶原蛋白是从短嘴鱼皮中提取的。计算机模拟方法表明,短嘴矛鱼V型胶原蛋白具有很高的血管紧张素转换酶(ACE)抑制活性(79.50%),二肽基肽酶IV抑制(74.91%)活性,抗血栓活性(46.83%)。本研究的结构澄清和可能的功能研究为源自鱼源的外源V型胶原蛋白的应用提供了基础。
Type V collagen is considered to be a crucial minor collagen in fish skin with unique physiological functions. In this research, the cDNAs of three procollagens (Tacol5a1, Tacol5a2, and Tacol5a3) in type V collagen were cloned from the skin of shortbill spearfish (Tetrapturus angustirostris). The open reading frames (ORFs) of Tacol5a1, Tacol5a2, and Tacol5a3 contained 5991, 4485, and 5607 bps, respectively, encoding 1997, 1495, and 1869 amino acid residues. Each of the deduced amino acid sequences of procollagens contained a signal peptide and a fibrillar collagen C-terminal domain (COLFI). A conserved thrombospondin-like N-terminal domain (TSPN) was found at the N-terminus of Tacol5a1 and 5a3 procollagens, whereas a von Willebrand factor (VWC) was found at the N-terminus of Tacol5a2 procollagen. Tacol5a1, Tacol5a2, and Tacol5a3 had their theoretical isoelectric points of 5.06, 6.75, and 5.76, respectively, and predicted molecular weights of 198,435.60, 145,058.48, and 189,171.18, respectively. The phylogenetic tree analysis revealed that Tacol5a1 of shortbill spearfish clustered with that of yellow perch (Perca flavescens) instead of broadbill swordfish (Xiphias gladius). In addition, type V collagen was extracted from the shortbill spearfish skin. The in silico method demonstrated that shortbill spearfish type V collagen has a high potential for angiotensin-converting enzyme (ACE) inhibition activity (79.50%), dipeptidyl peptidase IV inhibition (74.91%) activity, and antithrombotic activity (46.83%). The structural clarification and possible functional investigation in this study provide the foundation for the applications of exogenous type V collagen derived from fish sources.