S. cerevisiae Vts1p induces deadenylation-dependent transcript degradation and interacts with the Ccr4p-Pop2p-Not deadenylase complex.
The Smaug family of sequence-specific RNA binding proteins regulates mRNA translation and degradation by binding to consensus stem-loop structures in target mRNAs. Vts1p is a member of the Smaug protein family that regulates the stability of target transcripts in Saccharomyces cerevisiae. Here we focus on the mechanism of Vts1p-mediated mRNA decay. Using RNA reporters that recapitulate Vts1p-mediated decay in vivo, we demonstrate that Vts1p stimulates mRNA degradation through deadenylation mediated by the Ccr4p-Pop2p-Not deadenylase complex. We also show that Vts1p interacts with the Ccr4p-Pop2p-Not complex suggesting that Vts1p recruits the Ccr4p-Pop2p-Not deadenylase complex to target mRNAs, resulting in transcript decay. Following deadenylation Vts1p target transcripts are decapped and subsequently degraded by the 5'-to-3' exonuclease Xrn1p. Decapping and 5'-to-3' decay is thought to occur in foci known as P-bodies, and we provide evidence that Vts1p function may involve P-bodies. Taken together with previous work, these data suggest that Smaug family members employ a conserved mechanism to induce transcript degradation that involves recruitment of the Ccr4-Pop2-Not deadenylase to target mRNAs.
Rendl
Laura M
LM
Department of Biochemistry, University of Toronto, Toronto, Ontario M5S 1A8, Canada.
Bieman
Melissa A
MA
Smibert
Craig A
CA
D009097:Multienzyme Complexes / Q000378:metabolism; D020871:RNA Stability; D012333:RNA, Messenger / Q000378:metabolism; D016601:RNA-Binding Proteins; D012260:Ribonucleases / Q000378:metabolism*; D012441:Saccharomyces cerevisiae; D029701:Saccharomyces cerevisiae Proteins / Q000378:metabolism*
D009097:Multienzyme Complexes; D012333:RNA, Messenger; D016601:RNA-Binding Proteins; D029701:Saccharomyces cerevisiae Proteins; C508663:Vts1 protein, S cerevisiae; C078657:CCR4 protein, S cerevisiae; D012260:Ribonucleases; C445084:mRNA deadenylase; C079009:POP2 protein, S cerevisiae