Activation of the transcription of Gal4-regulated genes by Physarum 14-3-3 in yeast is related to dimer-binding motif-2 and three phosphorylation sites.
Arch Microbiol
; 192(1): 33-40, 2010 Jan.
Article
em En
| MEDLINE
| ID: mdl-19936707
ABSTRACT
The roles of 14-3-3 proteins in the lower eukaryotes are still elusive. We isolated a cDNA encoding the 14-3-3 protein (P14-3-3) from the lower eukaryote Physarum polycephalum. This P14-3-3 gene was then inserted downstream of the Gal4 DNA-binding domain in the yeast expression vector pGBKT7. The recombinant vector was transformed into auxotrophic AH109 and Y187 yeast cells to detect the activation of Gal4-regulated gene expression mediated by P14-3-3. The results showed that three reporter genes (ADE2, HIS3, and lacZ) could be normally expressed, indicating that the transcriptional activation function of P14-3-3 was retained. We subsequently used a truncated P14-3-3 peptides and mutant peptides to study the activation of the Gal4-regulated genes ADE2, HIS3, and lacZ. We found that deletion of the N-terminal second dimer-binding motif (DBM2) sequence or the C-terminal coil sequence led to the loss of P14-3-3's transcriptional activation function. Specifically, any mutation at the potential phosphorylation sites (Ser62 and Ser67) on DBM2 or at the C-terminal potential phosphorylation site (235ThrSer236) led to the loss of the transcriptional activation function of P14-3-3. Taken together, these observations suggest that the transcriptional activation function of P14-3-3 in lower eukaryotes is related to DBM2 and the C-terminal coil structures.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Proteínas de Protozoários
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Ativação Transcricional
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Physarum polycephalum
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Proteínas 14-3-3
Idioma:
En
Ano de publicação:
2010
Tipo de documento:
Article