Molecular cloning and expression analysis of the MaASR1 gene in banana and functional characterization under salt stress

Hongxia Miao,Wei Hu,Peiguang Sun,Biyu Xu,Zhiqiang Jin,Yuan Wang,Caihong Jia,Juhua Liu

doi:10.1016/j.ejbt.2014.09.002

Abstract

abstract Article history:Received 7 June 2014Accepted 13 August 2014Available online 18 September 2014Keywords:ASRBananaExpression patternsSalt resistance Background:Abscisicacid(ABA)-,stress-andripenin g-inducedprotein(ASR)isplant-speci ﬁchydrophilictranscriptionalregulatorsinvolvedinsucrosestr essandwoundinginbanana.However,itisnotknownwhetherbanana ASR genesconfersalt stress tolerance. The contexts of the study was to analysis the sequence characterization of banana ASR1,andidentifyits expression patterns and function under salt stress using quantitative real-time PCR (qPCR) and overexpression inArabidopsis . The purpose was to evaluate the role of banana ASR1 to salt stress tolerance employed by plants.Results: Afull-lengthcDNAisolatedfrombananafruitwasnamed MaASR1,andithada432bpopenreadingframe(ORF)encoding 143 amino acids. MaASR1 was preferential expression in roots and leaves compared to low expression in fruits,rhizomes and ﬂowers. Under salt stress, the expression of MaASR1 quickly increased and highest expression level wasdetected in roots and leaves at 4 h, and then gradually decreased. These results suggested that MaASR1 expression wasinduced under salt stress. MaASR1 protein was localized in the nucleus and plasma membrane. MaASR1 wastransformed to Arabidopsis and veri ﬁed by southern and northern analysis, tran sgenic lines L14 and L38 integrated oneand two copies of MaASR1, respectively, while overexpression in tran sgenic lines provided evidence for the role ofMaASR1 to salt stress tolerance.Conclusions: This study demonstrated that overexpression of MaASR1 in Arabidopsis confers salt stress tolerance byreducing the expression of ABA/stress -responsive genes, but does not affect the expression of the ABA-independentpathway and biosynth esis pathway genes.©2014Pontiﬁcia Universidad Catolica de Valparaiso. Production and hosting by Elsevier B.V. All rights reserved.

Highlights

High salt levels affect the growth and development of most plant species and cause significant losses in crop yield; plants self-regulate to cope with the negative responses of such salt stress [1, 2,3]
A full-length ASR gene was obtained from the banana fruit and designated as MaASR1
Sequence analysis revealed that the full-length MaASR1 cDNA has a 432 bp open reading frame (ORF) (Phred scores N 20) that encodes 143 amino acids

Summary

Introduction

High salt levels affect the growth and development of most plant species and cause significant losses in crop yield; plants self-regulate to cope with the negative responses of such salt stress [1, 2,3]. Abscisic acid (ABA)-, stress- and ripening-induced protein (ASR) is plant-specific hydrophilic transcriptional regulators involved in sucrose stress and wounding in banana. It is not known whether banana ASR genes confer salt stress tolerance. The expression of MaASR1 quickly increased and highest expression level was detected in roots and leaves at 4 h, and gradually decreased. Conclusions: This study demonstrated that overexpression of MaASR1 in Arabidopsis confers salt stress tolerance by reducing the expression of ABA/stress-responsive genes, but does not affect the expression of the ABA-independent pathway and biosynthesis pathway genes

Methods

Results

Discussion

Conclusion