School of Genetics and Microbiology, Trinity College Dublin, College Green, Dublin 2, Ireland.
Nucleic Acids Res. 2012 Mar;40(6):2700-11. doi: 10.1093/nar/gkr1108. Epub 2011 Nov 28.
Yeast histone mRNAs are polyadenylated, yet factors such as Rrp6p and Trf4p, required for the 3'-end processing of non-polyadenylated RNAs, contribute to the cell cycle regulation of these transcripts. Here, we investigated the role of other known 3'-end processing/transcription termination factors of non-polyadenylated RNA in the biogenesis of histone mRNAs, specifically the Nab3p/Nrd1p/Sen1p complex. We also re-evaluated the polyadenylation status of these mRNAs during the cell cycle. Our analysis reveals that yeast histone mRNAs have shorter than average PolyA tails and the length of the PolyA tail varies during the cell cycle; S-phase histone mRNAs possess very short PolyA tails while in G1, the tail length is relatively longer. Inactivation of either Sen1p or Rrp6p leads to a decrease in the PolyA tail length of histone mRNAs. Our data also show that Sen1p contributes to 3'-end processing of histone primary transcripts. Thus, histone mRNAs are distinct from the general pool of yeast mRNAs and 3'-end processing and polyadenylation contribute to the cell cycle regulation of these transcripts.
酵母组蛋白 mRNAs 是多聚腺苷酸化的，但像 Rrp6p 和 Trf4p 等因子，这些因子对于非多聚腺苷酸化 RNA 的 3'-末端加工是必需的，它们有助于这些转录物的细胞周期调控。在这里，我们研究了其他已知的非多聚腺苷酸化 RNA 的 3'-末端加工/转录终止因子在组蛋白 mRNAs 生物发生中的作用，特别是 Nab3p/Nrd1p/Sen1p 复合物。我们还重新评估了这些 mRNA 在细胞周期中的多聚腺苷酸化状态。我们的分析表明，酵母组蛋白 mRNAs 的 PolyA 尾巴比平均长度短，并且在细胞周期中 PolyA 尾巴的长度会发生变化；S 期组蛋白 mRNAs 的 PolyA 尾巴非常短，而在 G1 期，尾巴长度相对较长。Sen1p 或 Rrp6p 的失活会导致组蛋白 mRNAs 的 PolyA 尾巴长度减少。我们的数据还表明，Sen1p 有助于组蛋白初级转录物的 3'-末端加工。因此，组蛋白 mRNAs 与酵母 mRNA 的一般池不同，3'-末端加工和多聚腺苷酸化有助于这些转录物的细胞周期调控。
