梭梭SCARECROW-like 30基因的克隆、表达及功能分析

Cloning,expression and functional analysis of SCARECROW-like 30 gene from Haloxylon ammodendron

SCARECROW-like(SCL)是GRAS转录因子中的重要成员,主要参与植物生长发育、逆境胁迫响应以及赤霉素(GA)信号转导调控等。本研究基于梭梭转录组数据克隆获得1条在干旱胁迫下显著上调表达的SCL基因,并命名为HaSCL30。HaSCL30全长编码序列(CDS)为2109 bp,编码702个氨基酸,预测蛋白分子量为78.37 kDa,理论等电点为5.57,为不稳定亲水性蛋白,具有GRAS超家族保守结构域。多序列比对及系统进化表明梭梭HaSCL30蛋白与同为C4植物的玉米ZmSCL30及同科植物甜菜BvSCL30同源性较高、亲缘关系较近。STRING蛋白互作分析预测出SCL30蛋白与转录因子WRKY33和ERF104具有共表达特征。HaSCL30基因在梭梭不同组织(子叶、同化枝及根)均有表达,在子叶中相对表达量最高。在干旱和盐胁迫下HaSCL30出现不同程度上调表达。亚细胞定位结果表明HaSCL30定位于细胞核和细胞膜。酵母异源表达结果显示,过表达HaSCL30能提高酵母耐盐和耐旱性。基于以上结果,HaSCL30可能参与荒漠植物梭梭的高盐、干旱胁迫响应,对其荒漠环境生存能力的提高存在正向调控作用。研究结果为进一步揭示HaSCL30在梭梭抗旱耐盐中的功能及作用机制提供依据。

SCARECROW-like(SCL)is an important member of GRAS transcription factors,which is mainly involved in plant growth and development,stress response,and GA signal transduction.In this study,the SCL(named HaSCL30)with significant up-regulation was cloned from Haloxylon ammodendron through the transcriptome data of drought stress.The coding sequence(CDS)of HaSCL30 was 2109 bp,encoding 702 amino acids with molecular weight of 78.37 kDa and theoretical isoelectric point of 5.57.HaSCL30protein is an unstable hydrophile protein with GRAS superfamily conserved domain.Multiple sequence alignment and phylogenetic tree results showed that HaSCL30 was highly homologous and close to the ZmSCL30 from maize which is a C4 plant as same as H.ammodendron and the BvSCL30 from Chenopodiaceae which is in the same family.STRING protein interaction analysis predicted that SCL30 protein as well as transcription factor WRKY33 and ERF104 have common expression characteristics.Gene expression analysis showed that HaSCL30 was expressed in different tissues(cotyledons,assimilation branches and roots),and the highest expression level was found in cotyledons.In addition,HaSCL30 gene was up-regulated in different degrees under drought and salt stress.The results of subcellular localization showed that HaSCL30 located in the nucleus and cell membrane.The overexpression of HaSCL30 could improve the salt tolerance and drought tolerance of yeast.The results indicated that HaSCL30 gene was involved in plant growth and response to salt and drought stress,which has a positive regulating effect on the improvement of its desert environmental survivability.This study provides a basis for further revealing the function and action mechanism of HaSCL30 in the drought and salt resistance of H.ammodendron.