Unknown,Transcriptomics,Genomics,Proteomics

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ß-amylase1 mutant Arabidopsis plants show improved drought tolerance due to reduced starch breakdown in guard cells

ABSTRACT: In plants, drought stress is a major growth limiting factor causing cell water loss through open stomata. In this study, guard cell-specific transcripts from drought-stressed Arabidopsis plants were analyzed and a down-regulation of β-amylase 1 (BAM1) was found. In previous studies, BAM1 was shown to be involved in stomatal starch degradation under ambient conditions. Impaired starch breakdown of bam1 mutant plants was accompanied by decreased stomatal opening. Here, we show that drought tolerance of bam1 mutant plants is improved as compared to wild type controls. Microarray-analysis of stomata-specific transcripts from bam1 mutant plants revealed a significant down-regulation of genes encoding aquaporins, auxin- and ethylene-responsive factors and cell-wall modifying enzymes. This expression pattern suggests that reduced water-uptake and limited cell wall extension are associated with the closed state of stomata of bam1 mutant plants. Together these data suggest that regulation of stomata-specific starch turnover is important for adapting stomata opening to environmental needs and its breeding manipulation may result in drought tolerant crop plants. Stress induced gene expression in Arabidopsis stomata was measured after exposure to single heat stress. Heat stress conditions were analyzed for both Col-0 plants and a T-DNA insertion line for β-amylase 1. Three days before harvesting heat stress was applied (32°C/28°C). Samples were taken by pooling the stomata of six to eight leaves per sample.

ORGANISM(S): Arabidopsis thaliana

SUBMITTER: Christian Prasch

PROVIDER: E-GEOD-66105 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

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ß-amylase1 mutant Arabidopsis plants show improved drought tolerance due to reduced starch breakdown in guard cells

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