Monitoring the expression profiles of 7000 <i>Arabidopsis</i> genes under drought, cold and high‐salinity stresses using a full‐length cDNA microarray

TLDR

Full‑length cDNAs are essential for functional analysis of Arabidopsis genes, and cDNA microarrays have been developed for quantitative, global expression profiling. The authors constructed a 7,000‑member full‑length cDNA microarray to monitor gene expression in Arabidopsis under drought, cold, and high‑salinity stresses over time. The array revealed that 53, 277, and 194 genes were up‑regulated more than five‑fold by cold, drought, and high‑salinity, respectively, with 22 genes responsive to all three stresses, distinct expression clusters—including a DREB1A‑peaking group at 2 h—and 40 transcription factors (~11 %) among the stress‑inducible genes.

Abstract

Summary Full‐length cDNAs are essential for functional analysis of plant genes in the post‐sequencing era of the Arabidopsis genome. Recently, cDNA microarray analysis has been developed for quantitative analysis of global and simultaneous analysis of expression profiles. We have prepared a full‐length cDNA microarray containing ≈7000 independent, full‐length cDNA groups to analyse the expression profiles of genes under drought, cold (low temperature) and high‐salinity stress conditions over time. The transcripts of 53, 277 and 194 genes increased after cold, drought and high‐salinity treatments, respectively, more than fivefold compared with the control genes. We also identified many highly drought‐, cold‐ or high‐salinity‐ stress‐inducible genes. However, we observed strong relationships in the expression of these stress‐responsive genes based on Venn diagram analysis, and found 22 stress‐inducible genes that responded to all three stresses. Several gene groups showing different expression profiles were identified by analysis of their expression patterns during stress‐responsive gene induction. The cold‐inducible genes were classified into at least two gene groups from their expression profiles. DREB1A was included in a group whose expression peaked at 2 h after cold treatment. Among the drought, cold or high‐salinity stress‐inducible genes identified, we found 40 transcription factor genes (corresponding to ≈11% of all stress‐inducible genes identified), suggesting that various transcriptional regulatory mechanisms function in the drought, cold or high‐salinity stress signal transduction pathways.