Function of the Ski4p (Csl4p) and Ski7p Proteins in 3′-to-5′ Degradation of mRNA Journal Article uri icon



  • ABSTRACT; ; One of two general pathways of mRNA decay in the yeast; Saccharomyces cerevisiae; occurs by deadenylation followed by 3′-to-5′ degradation of the mRNA body. Previous results have shown that this degradation requires components of the exosome and the Ski2p, Ski3p, and Ski8p proteins, which were originally identified due to their superkiller phenotype. In this work, we demonstrate that deletion of the; SKI7; gene, which encodes a putative GTPase, also causes a defect in 3′-to-5′ degradation of mRNA. Deletion of; SKI7; , like deletion of; SKI2; ,; SKI3; , or; SKI8; , does not affect various RNA-processing reactions of the exosome. In addition, we show that a mutation in the; SKI4; gene also causes a defect in 3′-to-5′ mRNA degradation. We show that the; SKI4; gene is identical to the; CSL4; gene, which encodes a core component of the exosome. Interestingly, the; ski4-1; allele contains a point mutation resulting in a mutation in the putative RNA binding domain of the Csl4p protein. This point mutation strongly affects mRNA degradation without affecting exosome function in rRNA or snRNA processing, 5′ externally transcribed spacer (ETS) degradation, or viability. In contrast, the; csl4-1; allele of the same gene affects rRNA processing but not 3′-to-5′ mRNA degradation. We identify; csl4-1; as resulting from a partial-loss-of-function mutation in the promoter of the; CSL4; gene. These data indicate that the distinct functions of the exosome can be separated genetically and suggest that the RNA binding domain of Csl4p may have a specific function in mRNA degradation.;

publication date

  • November 1, 2000

Date in CU Experts

  • February 21, 2014 10:29 AM

Full Author List

  • van Hoof A; Staples RR; Baker RE; Parker R

author count

  • 4

Other Profiles

International Standard Serial Number (ISSN)

  • 0270-7306

Electronic International Standard Serial Number (EISSN)

  • 1098-5549

Additional Document Info

start page

  • 8230

end page

  • 8243


  • 20


  • 21