Transcript profiling reveals diverse roles of auxin-responsive genes during reproductive development and abiotic stress in rice.
Auxin influences growth and development in plants by altering gene expression. Many auxin-responsive genes have been characterized in Arabidopsis in detail, but not in crop plants. Earlier, we reported the identification and characterization of the members of the GH3, Aux/IAA and SAUR gene families in rice. In this study, whole genome microarray analysis of auxin-responsive genes in rice was performed, with the aim of gaining some insight into the mechanism of auxin action. A comparison of expression profiles of untreated and auxin-treated rice seedlings identified 315 probe sets representing 298 (225 upregulated and 73 downregulated) unique genes as auxin-responsive. Functional categorization revealed that genes involved in various biological processes, including metabolism, transcription, signal transduction, and transport, are regulated by auxin. The expression profiles of auxin-responsive genes identified in this study and those of the members of the GH3, Aux/IAA, SAUR and ARF gene families were analyzed during various stages of vegetative and reproductive (panicle and seed) development by employing microarray analysis. Many of these genes are, indeed, expressed in a tissue-specific or developmental stage-specific manner, and the expression profiles of some of the representative genes were confirmed by real-time PCR. The differential expression of auxin-responsive genes during various stages of panicle and seed development implies their involvement in diverse developmental processes. Moreover, several auxin-responsive genes were differentially expressed under various abiotic stress conditions, indicating crosstalk between auxin and abiotic stress signaling.
Jain
Mukesh
M
National Institute of Plant Genome Research (NIPGR), Aruna Asaf Ali Marg, New Delhi, India. mjain@nipgr.res.in
Khurana
Jitendra P
JP
D016000:Cluster Analysis; D003080:Cold Temperature; D020869:Gene Expression Profiling; D018507:Gene Expression Regulation, Developmental / Q000187:drug effects; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D007210:Indoleacetic Acids / Q000494:pharmacology*; D020411:Oligonucleotide Array Sequence Analysis / Q000379:methods*; D012275:Oryza / Q000235:genetics* / Q000254:growth & development; D010937:Plant Growth Regulators / Q000494:pharmacology; D018515:Plant Leaves / Q000235:genetics / Q000254:growth & development; D018517:Plant Roots / Q000235:genetics / Q000254:growth & development; D012098:Reproduction / Q000187:drug effects / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012965:Sodium Chloride / Q000494:pharmacology
D007210:Indoleacetic Acids; D010937:Plant Growth Regulators; D012965:Sodium Chloride