Functional features of the C-terminal region of yeast ribosomal protein L5.
Mol Genet Genomics
; 280(4): 337-50, 2008 Oct.
Article
em En
| MEDLINE
| ID: mdl-18751732
ABSTRACT
The aim of this study was to analyze the functional importance of the C-terminus of the essential yeast ribosomal protein L5 (YrpL5). Previous studies have indicated that the C-terminal region of YrpL5 forms an alpha-helix with a positively charged surface that is involved in protein-5S rRNA interaction. Formation of an YrpL5.5S rRNA complex is a prerequisite for nuclear import of YrpL5. Here we have tested the importance of the alpha-helix and the positively charged surface for YrpL5 function in Saccharomyces cerevisiae using site directed mutagenesis in combination with functional complementation. Alterations in the sequence forming the putative alpha-helix affected the functional capacity of YrpL5. However, the effect did not correlate with a decreased ability of the protein to bind to 5S rRNA as all rpL5 mutants tested were imported to the nucleus whether or not the alpha-helix or the positively charged surface were intact. The alterations introduced in the C-terminal sequence affected the growth rate of cells expressing mutant but functional forms of YrpL5. The reduced growth rate was correlated with a reduced ribosomal content per cell indicating that the alterations introduced in the C-terminus interfered with ribosome assembly.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Proteínas Ribossômicas
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Saccharomyces cerevisiae
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RNA Fúngico
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RNA Ribossômico 5S
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Núcleo Celular
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Proteínas de Saccharomyces cerevisiae
Idioma:
En
Ano de publicação:
2008
Tipo de documento:
Article