The Schizosaccharomyces pombe fusion gene hal3 encodes three distinct activities.
Mol Microbiol
; 90(2): 367-82, 2013 Oct.
Article
em En
| MEDLINE
| ID: mdl-23962284
ABSTRACT
Saccharomyces cerevisiaeâ
Hal3 and Vhs3 are moonlighting proteins, forming an atypical heterotrimeric decarboxylase (PPCDC) required for CoA biosynthesis, and regulating cation homeostasis by inhibition of the Ppz1 phosphatase. The Schizosaccharomyces pombeâ
ORF SPAC15E1.04 (renamed as Spâ
hal3) encodes a protein whose amino-terminal half is similar to Sc Hal3 whereas its carboxyl-terminal half is related to thymidylate synthase (TS). We show that Spâ
Hal3 and/or its N-terminal domain retain the ability to bind to and modestly inhibit in vitro S. cerevisiaeâ
Ppz1 as well as its S. pombe homolog Pzh1, and also exhibit PPCDC activity in vitro and provide PPCDC function in vivo, indicating that Spâ
Hal3 is a monogenic PPCDC in fission yeast. Whereas the Sp Hal3 N-terminal domain partially mimics Sc Hal3 functions, the entire protein and its carboxyl-terminal domain rescue the S. cerevisiaeâ
cdc21 mutant, thus proving TS function. Additionally, we show that the 70 kDa Sp Hal3 protein is not proteolytically processed under diverse forms of stress and that, as predicted, Spâ
hal3 is an essential gene. Therefore, Spâ
hal3 represents a fusion event that joined three different functional activities in the same gene. The possible advantage derived from this surprising combination of essential proteins is discussed.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Schizosaccharomyces
/
Timidilato Sintase
/
Carboxiliases
/
Proteínas de Schizosaccharomyces pombe
/
Fusão Gênica
/
Genes Fúngicos
Idioma:
En
Revista:
Mol Microbiol
Assunto da revista:
BIOLOGIA MOLECULAR
/
MICROBIOLOGIA
Ano de publicação:
2013
Tipo de documento:
Article
País de afiliação:
Espanha