Kashima Simone, Soares Andreimar M, Roberto Patrícia G, Pereira José O, Astolfi-Filho Spartaco, Cintra Adélia O, Fontes Marcos R M, Giglio José R, de Castro França Suzelei
Departamento de Biotecnologia, Universidade de Ribeirão Preto, UNAERP, Av Costábile Romano, 2201, 14096-380 Ribeirão Preto, SP, Brazil.
Biochimie. 2002 Jul;84(7):675-80. doi: 10.1016/s0300-9084(02)01429-3.
The complete nucleotide sequence of a nerve growth factor precursor from Bothrops jararacussu snake (Bj-NGF) was determined by DNA sequencing of a clone from cDNA library prepared from the poly(A) + RNA of the venom gland of B. jararacussu. cDNA encoding Bj-NGF precursor contained 723 bp in length, which encoded a prepro-NGF molecule with 241 amino acid residues. The mature Bj-NGF molecule was composed of 118 amino acid residues with theoretical pI and molecular weight of 8.31 and 13,537, respectively. Its amino acid sequence showed 97%, 96%, 93%, 86%, 78%, 74%, 76%, 76% and 55% sequential similarities with NGFs from Crotalus durissus terrificus, Agkistrodon halys pallas, Daboia (Vipera) russelli russelli, Bungarus multicinctus, Naja sp., mouse, human, bovine and cat, respectively. Phylogenetic analyses based on the amino acid sequences of 15 NGFs separate the Elapidae family (Naja and Bungarus) from those Crotalidae snakes (Bothrops, Crotalus and Agkistrodon). The three-dimensional structure of mature Bj-NGF was modeled based on the crystal structure of the human NGF. The model reveals that the core of NGF, formed by a pair of beta-sheets, is highly conserved and the major mutations are both at the three beta-hairpin loops and at the reverse turn.
通过对从巴西矛头蝮蛇毒腺的聚腺苷酸加尾RNA制备的cDNA文库中的一个克隆进行DNA测序，确定了巴西矛头蝮蛇神经生长因子前体（Bj-NGF）的完整核苷酸序列。编码Bj-NGF前体的cDNA长度为723 bp，编码一个具有241个氨基酸残基的前原神经生长因子分子。成熟的Bj-NGF分子由118个氨基酸残基组成，理论上的等电点和分子量分别为8.31和13,537。其氨基酸序列与杜氏响尾蛇、白眉蝮蛇、罗素蝰蛇、多环眼镜蛇、眼镜蛇属、小鼠、人类、牛和猫的神经生长因子的序列相似性分别为97%、96%、93%、86%、78%、74%、76%、76%和55%。基于15种神经生长因子氨基酸序列的系统发育分析将眼镜蛇科（眼镜蛇属和环蛇属）与蝰蛇科蛇（矛头蝮属、响尾蛇属和蝮蛇属）区分开来。基于人类神经生长因子的晶体结构对成熟Bj-NGF的三维结构进行了建模。该模型显示，由一对β-折叠形成的神经生长因子核心高度保守，主要突变位于三个β-发夹环和反向转角处。
