Biomineralization mechanism and evolution of nano-structured habu snake venom fang

有毒动物不仅具有产毒腺，还具有注毒器官，如毒牙、毒囊等，可有效地向猎物注射毒液。 本研究采用蛋白质组学和转录组学相结合的方法，对黄绿原棘头蛇（Protobothrops flavoviridis，habu）毒牙基质蛋白的结构和性质进行了分析。 2D-PAGE显示20多个蛋白质点，等电点为4 ~ 5，分子量为25- 55 kDa，主要成分为Ⅰ型胶原。 此外，生物矿化相关的蛋白质，如骨调节蛋白，IMPG 2，牙本质基质蛋白1等，通过RNA测序分析从成牙组织的转录产物中鉴定。

Venomous animals have not only the venom-producing gland but also venome-injecting organs such as venom-loaded fangs and nematocyst for the efficient venome-injection to prey species. Although it is considered that the venom fang have evolved functionally from teeth, their biomineralization mechanisms are still unknown.In this study, to clarify the structure and properties of the matrix proteins from Protobothrops flavoviridis (habu) snake venom fangs were analysed by combined proteomic and transcriptomics analyses.Venom-loaded fangs were calcified with 50% formic acid, and their proteins were extracted by 8M urea. 2D-PAGE showed the more than 20 protein spots with the isoelectric point ranging 4 to 5 and molecular weight of 25-55kDa including type I collagen as a major component. Furthermore, the biomineralization related proteins such as osteomodulin, IMPG2, dentin matrix protein 1 etc. were identified from transcription products by RNA-seq analysis of fang-forming tissues.