Related domains in yeast tRNA ligase, bacteriophage T4 polynucleotide kinase and RNA ligase, and mammalian myelin 2',3/‐cyclic nucleotide phosphohydrolase revealed by amino acid squence comparison

FEBS Letters

Gorbalenya, Alexander E.¹  Koonin, Eugene V.² 

[1] Institute of Poliomyelitis and Viral Encephalitides, USSR Academy of Medical Sciences, 142782 Moscow Region, USSR;Institute of Microbiology, The USSR Academy of Sciences, 7 Prospekt 60let Oktyabrya, 117811 MoscowUSSR

关键词: CNPase;    Myelin;    Polynucleotide kinase;    tRNA ligase;    tRNA splicing;    CNPase;    2';    3'-cyclic nucleotide 3 '-phosphohydrolase;    PNK;    polynucleotide kinase;   

DOI  :  10.1016/0014-5793(90)81015-G

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Related domains containing the purine NTP-binding sequence pattern have been revealed in two enzymes involved in tRNA processing, yeast tRNA ligase and phage T4 polynucleotide kinase, and in one of the major proteins of mammalian nerve myelin sheath, 2',3'-cyclic nucleotide 3'-phospho-hydrolase (CNPase). It is suggested that, similarly to the tRNA processing enzymes, CNPase possesses polynucleotide kinase activity, in addition to the phosphohydrolase one. It is speculated that CNPase may be an authentic mammalian polynucleotide kinase recruited as a structural component of the myelin sheath, analogously to the eye lens crystallins. Significant sequence similarity was revealed also between the N-terminal regions of yeast tRNA ligase and phage T4 RNA ligase. A tentative scheme of the domainal organizations for the three complex enzymes is proposed. According to this model, tRNA ligase contains at least three functional domains, in the order: N-ligase-kinase-phosphohydrolase-C, whereas poly-nucleotide kinase and CNPase encompass only the two C-terminal domains in the same order.

【 授权许可】

Unknown