Graduate School of Science and Technology, Nara Institute of Science and Technology, Ikoma, 630-0192 Japan.
Plant Cell Physiol. 2021 Mar 25;62(1):143-155. doi: 10.1093/pcp/pcaa147.
Multiple mechanisms are involved in gene expression, with mRNA degradation being critical for the control of mRNA accumulation. In plants, although some trans-acting factors and motif sequences have been identified in deadenylation-dependent mRNA degradation, endonucleolytic cleavage-dependent mRNA degradation has not been studied in detail. Previously, we developed truncated RNA-end sequencing (TREseq) in Arabidopsis thaliana and detected G-rich sequence motifs around 5' degradation intermediates. However, it remained to be elucidated whether degradation efficiencies of 5' degradation intermediates in A. thaliana vary among growth conditions and developmental stages. To address this issue, we conducted TREseq of cultured cells under heat stress and at three developmental stages (seedlings, expanding leaves and expanded leaves) and compared 5' degradation intermediates data among the samples. Although some 5' degradation intermediates had almost identical degradation efficiencies, others differed among conditions. We focused on the genes and sites whose degradation efficiencies differed. Changes in degradation efficiencies at the gene and site levels revealed an effect on mRNA accumulation in all comparisons. These changes in degradation efficiencies involved multiple determinants, including mRNA length and translation efficiency. These results suggest that several determinants govern the efficiency of mRNA degradation in plants, helping the organism to adapt to varying conditions by controlling mRNA accumulation.
多个机制参与基因表达，mRNA 降解对于 mRNA 积累的控制至关重要。在植物中，尽管已经鉴定了一些依赖脱腺苷酸化的 mRNA 降解的反式作用因子和基序序列，但对依赖内切核酸酶切割的 mRNA 降解尚未进行详细研究。先前，我们在拟南芥中开发了截断 RNA 末端测序 (TREseq)，并在 5'降解中间产物周围检测到富含 G 的序列基序。然而，仍有待阐明拟南芥 5'降解中间产物的降解效率是否因生长条件和发育阶段而异。为了解决这个问题，我们在热应激和三个发育阶段（幼苗、扩展叶和展开叶）下对培养细胞进行 TREseq，并比较了样品之间的 5'降解中间产物数据。尽管一些 5'降解中间产物的降解效率几乎相同，但其他降解效率在不同条件下有所不同。我们专注于降解效率不同的基因和位点。基因和位点水平的降解效率变化揭示了所有比较中 mRNA 积累的影响。这些降解效率的变化涉及多个决定因素，包括 mRNA 长度和翻译效率。这些结果表明，几个决定因素控制着植物中 mRNA 降解的效率，有助于通过控制 mRNA 积累使生物体适应不同的条件。
