Yeast lsm pro-apoptotic mutants show defects in S-phase entry and progression

• DOI: 10.4161/cc.9.19.13210
• Publication Date: 2010-10-07T18:33:55Z
• Authors: Vanessa Palermo; Enrico Cundari; Eleonora Mangiapelo; Claudio Falcone; Cristina Mazzoni
• Keywords: Histone deacetylase 5; Exosome complex

Expression of the histone genes is tightly coupled to rates DNA synthesis in yeast and mRNAs are modulated both transcriptionally post-transcriptionally. Trf4 Trf5, poly(A) polymerases, that mediates polyadenylation consequent degradation) Rrp6, an exosome component, play a role regulation mRNA levels. In this paper we show degradation mutant Kllsm4Δ1, induced early S-phase maintained at high level all along entire cell cycle due delay exit from and/or entry into M-phase. The overexpression HIR1 gene (Histone transcriptional repressor), previously isolated as multicopy suppressor apoptotic phenotypes observed can also restore normal cycling expression. We found low doses hydroxyurea neutralize onset well another decapping mutants (lsm1) and, addition, increase chronological lifespan strains suggesting S phase recover some cellular defects mutants.