来自人类精子的P2鱼精蛋白是具有一个CYS2/HIS2基序的锌指蛋白。

P2 protamines from human sperm are zinc -finger proteins with one CYS2/HIS2 motif.

作者信息

Bianchi F, Rousseaux-Prevost R, Sautiere P, Rousseaux J

机构信息

URA CNRS 409, Institut de Recherche sur le Cancer, Lille, France.

出版信息

Biochem Biophys Res Commun. 1992 Jan 31;182(2):540-7. doi: 10.1016/0006-291x(92)91766-j.

DOI:10.1016/0006-291x(92)91766-j

PMID:1734868

Abstract

P1 (HP1) and P2 (HP2, HP3, HP4) protamines were isolated from human sperm nuclei in the reduced form and their interaction with zinc and cobalt was studied. One zinc atom per molecule of P2 protamines but not of P1 protamine was found. Absorption spectra of P2 protamines with cobalt were characteristic of a tetrahedral complex involving two histidine and two cysteine residues and with one cobalt per molecule. A tetrahedral complex was found neither in P1 protamines nor in P2 protamines alkylated at cysteine or at histidine residues. The zinc finger motif Cys2/His2 of P2 protamines may play a role in stabilization of human sperm chromatin and in inhibition of transcription.

摘要

从人精子细胞核中分离出还原形式的P1（HP1）和P2（HP2、HP3、HP4）鱼精蛋白，并研究了它们与锌和钴的相互作用。发现每分子P2鱼精蛋白含有一个锌原子，而P1鱼精蛋白不含锌原子。P2鱼精蛋白与钴的吸收光谱具有四面体络合物的特征，该络合物涉及两个组氨酸和两个半胱氨酸残基，且每分子含有一个钴。在P1鱼精蛋白中未发现四面体络合物，在半胱氨酸或组氨酸残基被烷基化的P2鱼精蛋白中也未发现。P2鱼精蛋白的锌指基序Cys2/His2可能在人精子染色质的稳定和转录抑制中发挥作用。