高粱窄叶突变体nal1表型鉴定及转录组分析

Phenotypic Identification and Transcriptome Analysis of the Narrow-leaf Mutant nal1 in Sorghum bicolor

为解析高粱窄叶的分子调控机制,挖掘影响高粱叶片发育的关键差异表达基因。利用0.1%EMS化学诱变野生型BTX623获得高粱窄叶突变体nal1(narrow leaf1),以野生型植株BTX623和窄叶突变体nal1为材料,对不同发育时期的叶片长、叶片宽、株高、穗长等性状进行表型分析。结果表明:与野生型BTX623的叶片相比,2叶1心时,窄叶突变体nal1的叶片开始变窄;开花期植株和成熟期植株叶片宽和叶片长差异极显著;成熟期窄叶突变体nal1穗较松散,但植株株高差异不显著。开花期剑叶转录组分析结果表明:高粱窄叶突变体nal1和野生型BTX623开花期剑叶共筛选到差异表达基因1 520个,通过KEGG、GO富集分析得出,功能注释基因显著富集在植物激素信号转导、玉米素生物合成、光合作用天线蛋白、次级代谢产物生物合成等通路上;进一步研究发现参与调控生长素和玉米素信号转导的差异表达基因有17个,参与调控玉米素生物合成的差异表达基因为7个,这些基因在窄叶突变体nal1中差异表达,直接影响生长素、玉米素的信号转导和玉米素的生物合成。因此推测突变体nal1通过调节生长素、玉米素的信号转导和玉米素的生物合成影响窄叶突变体nal1叶片的发育,进而突变体nal1出现叶片变窄的性状。

In order to analyze the molecular regulation mechanism of narrow leaves and explore the key differentially expressed genes that affect the development of leaves in Sorghum bicolor.We obtained the nal1(narrow leaf1)by 0.1%EMS chemical mutagenesis of BTX623.We analyzed the leaf length,leaf width,plant height,ear length and other characteristics of BTX623 and the nal1 at different development stages.Compared with the leaves of BTX623,the leaves of the nal1 began to narrow at the two leaves and one heart stage;There were significant differences in leaf width and length between flowering and mature plants;The spike of the nal1 was loose at maturity,but the difference of plant height was not significant.Transcriptome analysis of sword leaves showed that there were 1520 differentially expressed genes at the flowering stage between the nal1 and BTX623.According to KEGG and GO enrichment analyzing,annotated genes were significantly enriched in plant hormones,signal transduction,zeatin biosynthesis,photosynthetic antenna protein,secondary metabolite biosynthesis and other pathways.Further research found that there were 17 differentially expressed genes involved in the regulation of auxin signal transduction,zeatin signal transduction and 7 differentially expressed genes involved in the regulation of zeatin biosynthesis.It is possible to directly affect signal transduction of zeatin and biosynthesis of zeatin when these genes were differentially expressed in the nal1.So we speculated that it regulated the signal transduction of auxin and zeatin and the biosynthesis of zeatin,and then came out narrow leaf in the nal.