A dominant role for meiosis-specific 3 %26apos; RNA processing in controlling expression of a fission yeast cyclin gene

作者：Potter Kristine; Cremona Nicole; Sunder Sham; Wise Jo Ann^*

来源：RNA-A Publication of the RNA Society, 2012, 18(7): 1408-1420.

DOI：10.1261/rna.033423.112

• polyadenylation
• splicing
• fission yeast
• meiosis
• negative regulation

Meiotic gene regulation provides a rich source of insight into mechanisms of temporal control during development. We previously reported that accumulation of many meiotic mRNAs in fission yeast is governed by changes in 3%26apos; RNA processing and elucidated the molecular basis of this regulatory mechanism for an early meiotic gene. Here, we report that cleavage/polyadenylation is also the nexus of negative control for middle meiotic genes. Parallel profiles of splicing and polyadenylation are observed over a meiotic time course for both rem1 and spo4 but not for a constitutive control gene. Nevertheless, polyadenylation of rem1 transcripts is restricted to meiosis by a splicing-independent mechanism. Through systematic sequence substitutions, we identified a negative control region (NCR) located upstream of the rem1 transcription start site and found that it is required to block 3%26apos; RNA processing in proliferating cells. Ablation of the NCR relieves inhibition regardless of whether the intron is present, absent, or carries splice site mutations. Consistent with the previous report of a polypeptide encoded by the first exon of rem1, we discovered a second 3%26apos; processing site just downstream from the 5%26apos; splice site. Polyadenylation within the intron is activated concurrent with the downstream site during meiosis, is controlled by the NCR, and is enhanced when splicing is blocked via 5%26apos; junction or branch point mutations. Taken together, these data suggest a novel regulatory mechanism in which a 5%26apos; element modulates the dynamic interplay between splicing and polyadenylation.

• 出版日期2012-7