DOF-binding sites additively contribute to guard cell-specificity of AtMYB60promoter

BMC Plant Biology

Research Article

Alessandra Albertini¹  Chiara Tonelli¹  Lucio Conti²  Massimo Galbiati²  Eleonora Cominelli³  George Coupland⁴  Fabio Fornara⁵ 

[1] Dipartimento di Scienze Biomolecolari e Biotecnologie, Università degli Studi di Milano, Milano, Italy;Dipartimento di Scienze Biomolecolari e Biotecnologie, Università degli Studi di Milano, Milano, Italy;Fondazione Filarete, Milano, Italy;Dipartimento di Scienze Biomolecolari e Biotecnologie, Università degli Studi di Milano, Milano, Italy;Istituto di Biologia e Biotecnologia Agraria, CNR, Milano, Italy;Max Planck Institute for Plant Breeding Research, Cologne, Germany;Max Planck Institute for Plant Breeding Research, Cologne, Germany;Dipartimento di Biologia, Università degli Studi di Milano, Milano, Italy;

关键词: Guard Cell;    Minimal Promoter;    Chimeric Promoter;    Manipulate Gene Expression;    AAAG Motif;   

DOI  :  10.1186/1471-2229-11-162

 received in 2011-09-14, accepted in 2011-11-16,  发布年份 2011

来源: Springer

【 摘 要 】

BackgroundWe previously demonstrated that the Arabidopsis thaliana AtMYB60 protein is an R2R3MYB transcription factor required for stomatal opening. AtMYB60 is specifically expressed in guard cells and down-regulated at the transcriptional levels by the phytohormone ABA.ResultsTo investigate the molecular mechanisms governing AtMYB60 expression, its promoter was dissected through deletion and mutagenesis analyses. By studying different versions of AtMYB60 promoter::GUS reporter fusions in transgenic plants we were able to demonstrate a modular organization for the AtMYB60 promoter. Particularly we defined: a minimal promoter sufficient to confer guard cell-specific activity to the reporter gene; the distinct roles of different DOF-binding sites organised in a cluster in the minimal promoter in determining guard cell-specific expression; the promoter regions responsible for the enhancement of activity in guard cells; a promoter region responsible for the negative transcriptional regulation by ABA. Moreover from the analysis of single and multiple mutants we could rule out the involvement of a group of DOF proteins, known as CDFs, already characterised for their involvement in flowering time, in the regulation of AtMYB60 expression.ConclusionsThese findings shed light on the regulation of gene expression in guard cells and provide new promoter modules as useful tools for manipulating gene expression in guard cells, both for physiological studies and future biotechnological applications.

【 授权许可】

CC BY   
© Cominelli et al; licensee BioMed Central Ltd. 2011