Details

Autor(en) / Beteiligte

• Kennedy, Brian K
• Gotta, Monica
• Sinclair, David A
• Mills, Kevin
• McNabb, David S
• Murthy, Mala
• Pak, Sally M
• Laroche, Thierry
• Gasser, Susan M
• Guarente, Leonard

Titel

Redistribution of Silencing Proteins from Telomeres to the Nucleolus Is Associated with Extension of Life Span in S. cerevisiae

Ist Teil von

• Cell, 1997-05, Vol.89 (3), p.381-391

Ort / Verlag

United States: Elsevier Inc

Erscheinungsjahr

1997

Quelle

MEDLINE

Beschreibungen/Notizen

• A prior genetic study indicated that activity of Sir silencing proteins at a hypothetical AGE locus is essential for long life span. In this model, the SIR4-42 mutation would direct the Sir protein complex to the AGE locus, giving rise to a long life span. We show by indirect immunofluorescence that Sir3p and Sir4p are redirected to the nucleolus in the SIR4-42 mutant. Furthermore, this relocalization is dependent on both UTH4 a novel yeast gene that extends life span, and its homologue YGL023. Strikingly, the Sir complex is relocalized from telomeres to the nucleolus in old wild-type cells. We propose that the rDNA is the AGE locus and that nucleolar function is compromised in old yeast cells in a way that may be mitigated by targeting of Sir proteins to the nucleolus.