人类神经元蛋白 P17.3 全长 cDNA 的克隆及表达特征分析

Cloning and Expressional Characterization of a Full Length cDNA Encoding Human Neuronal Protein P17.3 (received Oct.8, 1998)

从人胎脑ｃＤＮＡ文库分离到一个长５９５ｂｐ的ｃＤＮＡ，它含一个编码１５３个氨基酸的完整开放阅读框，５ＵＴＲ长１８ｂｐ，３ＵＴＲ长１１８ｂｐ；在３ＵＴＲ中，含有非典型的加尾信号序列“ＡＡＴＴＡＡＡ”和长１５ｂｐ的ｐｏｌｙＡ序列。由阅读框推导的编码蛋白质的分子量为１７．３ＫＤ，等电点为４．８９。由于它与小鼠神经元蛋白ＮＰ１５．６呈高度同源，尤其是二者的推导氨基酸序列一致性高达８１．２％，故将这一新ｃＤＮＡ序列推导的蛋白命名为神经元蛋白Ｐ１７．３。用ＰＣＧＥＮＥ软件包的ＧＧＢＳＭ程序推导该蛋白质的二级结构，发现该蛋白中３２．６％的氨基酸参与组成α螺旋结构，１５．０％的氨基酸参与组成β折叠片；用位点检测分析软件的ＰＥＳＴＦＩＮＤ程序分析，发现它的第４８～６８位氨基酸残基区为快速衰变蛋白特征性的“ＰＥＳＴ”结构域。

A full length cDNA with 595bp was isolated from a human fetal brain cDNA library. It contains an open reading frame encoding 153 amino acids, with a 18bp 5UTR and a 118bp 3UTR in which there is an atypical polyadenylation signal (AATTAAA) and a 15bp poly(A) tail. The calculated molecular weight of the deduced protein is 17.3KD. The predicted isoelectric point is 4.89. On account of its high homologue to mouse neuronal protein NP15.6 and 81.2% identity between them, the deduced protein was named neuronal protein 17.3(in short, NP17.3). When its secondary structure was examined by the GGBSM program of PCGENE software, it was found that 32.6% and 15.0% of its amino acids were involved in forming α helix and β sheet respectively. Examined by PESTFIND program, a typical PEST region of rapidly degraded protein was found in its 48～68 residues.