Kuhn Josef M, Breton Ghislain, Schroeder Julian I
Division of Biological Sciences, Center for Molecular Genetics, University of California San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0116, USA.
Plant J. 2007 Jun;50(6):1049-62. doi: 10.1111/j.1365-313X.2007.03110.x. Epub 2007 May 3.
The precise regulation of RNA metabolism has crucial roles in numerous developmental and physiological processes such as the induction of flowering in plants. Here we report the identification of processes associated with mRNA metabolism of flowering-time regulators in wild-type Arabidopsis plants, which were revealed by an early flowering mutation, abh1, in an Arabidopsis nuclear mRNA cap-binding protein. By using abh1 as an enhancer of mRNA metabolism events, we identify non-coding polyadenylated cis natural antisense transcripts (cis-NATs) at the CONSTANS locus in wild-type plants. Our analyses also reveal a regulatory function of FLC intron 1 during transcript maturation in wild type. Moreover, transcripts encoding the FLM MADS box transcription factor are subject to premature intronic polyadenylation in wild type. In each case, abh1 showed altered patterns in RNA metabolism in these events compared with wild type. Together, abh1 enhances steps in the RNA metabolism that allowed us to identify novel molecular events of three key flowering-time regulators in wild-type plants, delivering important insights for further dissecting RNA-based mechanisms regulating flowering time in Arabidopsis.
RNA代谢的精确调控在众多发育和生理过程中起着关键作用，如植物开花的诱导。在此，我们报告了在野生型拟南芥植物中与开花时间调节因子的mRNA代谢相关过程的鉴定，这是由拟南芥核mRNA帽结合蛋白中的一个早花突变体abh1揭示的。通过将abh1用作mRNA代谢事件的增强子，我们在野生型植物的CONSTANS位点鉴定出非编码多聚腺苷酸化的顺式天然反义转录本（cis-NATs）。我们的分析还揭示了野生型中FLC内含子1在转录本成熟过程中的调控功能。此外，编码FLM MADS盒转录因子的转录本在野生型中会发生内含子过早多聚腺苷酸化。在每种情况下，与野生型相比，abh1在这些事件中的RNA代谢模式都发生了改变。总之，abh1增强了RNA代谢步骤，使我们能够鉴定野生型植物中三个关键开花时间调节因子的新分子事件，并为进一步剖析拟南芥中基于RNA的开花时间调控机制提供了重要见解。
