Kim Geun-Don, Cho Young-Hee, Lee Byeong-Ha, Yoo Sang-Dong
Division of Life Science, College of Life Science and Biotechnology, Korea University, Seoul, Korea (G.-D.K.; Y.-H.C.; S.-D.Y.); and.
Department of Life Science, Sogang University, Seoul, Korea (B.-H.L.).
Plant Physiol. 2017 Apr;173(4):2370-2382. doi: 10.1104/pp.16.01928. Epub 2017 Feb 21.
High-temperature stress often leads to differential RNA splicing, thus accumulating different types and/or amounts of mature mRNAs in eukaryotic cells. However, regulatory mechanisms underlying plant precursor mRNA (pre-mRNA) splicing in the environmental stress conditions remain elusive. Herein, we describe that a U5-snRNP-interacting protein homolog STABILIZED1 (STA1) has pre-mRNA splicing activity for heat-inducible transcripts including s and various s for the establishment of heat stress tolerance in Arabidopsis (). Our cell-based splicing reporter assay demonstrated STA1 acts on pre-mRNA splicing for specific subsets of stress-related genes. Cellular reconstitution of heat-inducible transcription cascades supported the view that STA1-dependent pre-mRNA splicing plays a role in DREB2A-dependent expression for heat-responsive gene expression. Further genetic analysis with a loss-of-function mutant -, -expressing transgenic plants in Col background, and -expressing transgenic plants in the - background verified that STA1 is essential in expression of necessary genes including for two-step heat stress tolerance in plants. However, constitutive overexpression of the cDNA version of in the - background is unable to execute plant heat stress tolerance in - Consistently our global target analysis of STA1 showed that its splicing activity modulates a rather broad range of gene expression in response to heat treatment. The findings of this study reveal that heat-inducible STA1 activity for pre-mRNA splicing serves as a molecular regulatory mechanism underlying the plant stress tolerance to high-temperature stress.
高温胁迫常常导致RNA可变剪接，从而使真核细胞中积累不同类型和/或数量的成熟mRNA。然而，在环境胁迫条件下植物前体mRNA（pre-mRNA）剪接的调控机制仍不清楚。在此，我们描述了一种与U5-snRNP相互作用的蛋白同源物稳定因子1（STA1）对热诱导转录本具有pre-mRNA剪接活性，这些转录本包括用于拟南芥热胁迫耐受性建立的s和各种s。我们基于细胞的剪接报告基因检测表明，STA1作用于应激相关基因特定亚群的pre-mRNA剪接。热诱导转录级联的细胞重建支持了这样一种观点，即STA1依赖的pre-mRNA剪接在依赖DREB2A的热响应基因表达的表达中起作用。利用功能缺失突变体、在Col背景中表达的转基因植物以及在背景中表达的转基因植物进行的进一步遗传分析证实，STA1对于植物两步热胁迫耐受性中包括等必需基因的表达至关重要。然而，在背景中组成型过表达cDNA版本的在中无法执行植物热胁迫耐受性。一致地，我们对STA1的全局靶点分析表明，其剪接活性响应热处理调节相当广泛的基因表达。本研究结果揭示，热诱导的STA1对pre-mRNA剪接的活性是植物对高温胁迫耐受性的分子调控机制。
