Functional and structural similarity between the X protein of hepatitis B virus and nucleoside diphosphate kinases

FEBS Letters

De-Medina, Tali¹  Shaul, Yosef¹ 

[1] Department of Molecular Genetics and Virology, The Weizmann Institute of Science, Rehovot 76100, Israel

关键词: Hepatitis B virus;    X protein;    NDPK;    Transcription;    Protein kinase;   

DOI  :  10.1016/0014-5793(94)00900-7

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

One of the four genes encoded by hepatitis B virus (HBV) is the regulatory 17 kDa protein called HBx (or pX). HBx is a transcription transactivator of many cellular and viral regulatory elements. We report here that recombinant HBx supports transcription in vitro and has phosphotransfer enzymatic activity. In the presence of EDTA, a phosphoryl-HBx is formed that releases the phosphate residue upon the addition of Mg²⁺. This two-step NTP hydrolysis reaction is characteristic of a group of enzymes termed nucleoside diphosphate kinases (NDPKs). Remarkably, structural similarity between HBx and NDPKs is also evident. Our findings suggest that HBx has evolved from this group of enzymes but acquired additional activities that satisfy the viral needs.

【 授权许可】

Unknown