Identified of a novel cis-element regulating the alternative splicing of LcDREB2.
Identified of a novel cis-element regulating the alternative splicing of LcDREB2.
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鉴定出调节 LcDREB2 选择性剪接的新型顺式元件
DOI：
10.1038/srep46106
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发表时间：
2017-04-06
影响因子：
4.6
通讯作者：
Liu G
中科院分区：
文献类型：
--
作者：
Liu Z;Yuan G;Liu S;Jia J;Cheng L;Qi D;Shen S;Peng X;Liu G
选择性剪接（alternative splicing，AS）是植物基因调控的重要机制。尽管AS广泛应用于植物基因表达调控，但在植物中鉴定AS机制中涉及的顺式元件的报道很少。为探讨羊草DREB 2同源基因LcDREB 2的AS调控机制，对LcDREB 2及其在禾本科植物中同源基因的基因组序列进行了比对，并在LcDREB 2的保守序列上引入了6个突变。通过分析LcDREB 2突变体在转基因水稻中的转录模式，发现了一个影响LcDREB 2 AS的顺式元件，即外显子剪接增强子1（Exonic Splicing Enhancer 1，ESE 1）。此外，电泳迁移率变动分析（EMSA）证实，5个富含丝氨酸精氨酸（SR）的蛋白质与ESE 1相互作用。为了进一步探讨DREB亚家族的表达调控机制，对DREB 2旁系同源基因进行了系统发育分析。这一结果有力地支持了AS在禾本科植物中是保守的，是一种调控基因功能表达的进化策略的假设。本研究的结果和方法将推动对植物AS调控机制的认识向前迈进一大步。
Alternative splicing (AS) is an important gene regulation mechanism in plants. Despite the widespread use of AS in plant gene expression regulation, the identification of the cis-elements involved in the AS mechanism is rarely reported in plants. To explore the regulation mechanism of the AS of LcDREB2, a DREB2 ortholog from Sheepgrass (Leymus chinensis), the genomic sequences of LcDREB2 and its homologs in Poaceae were aligned, and six mutations were introduced in the conserved sequence of LcDREB2. By analyzing the distinct transcript patterns of the LcDREB2 mutants in transgenic Oryza sativa, a novel cis-element that affected the AS of LcDREB2 was identified as Exonic Splicing Enhancer 1 (ESE1). In addition, five serine-arginine rich (SR) proteins were confirmed to interact with ESE1 by electrophoretic mobility shift assay (EMSA). To further explore the expression regulation mechanism of the DREB subfamily, phylogenetic analysis of DREB2 paralogous genes was performed. The results strongly supported the hypothesis that AS is conserved in Poaceae plants and that it is an evolutionary strategy for the regulation of the functional expression of genes. The findings and methods of our study will promote a substantial step forward in understanding of the plant AS regulation mechanism.