Unknown,Transcriptomics,Genomics,Proteomics

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Role of bHLH93 in controlling flowering time in Arabidopsis

ABSTRACT: Flowering in plants is a very dynamic and synchronized process where various cues including age, day-length, temperature and endogenous hormones fine-tune the timing of flowering for reproductive success. Arabidopsis thaliana is a facultative long day plant where long-day (LD) photoperiod promotes flowering. Arabidopsis still flowers under short-day (SD) conditions, albeit much later than LD conditions. Although, factors regulating the photoperiodic LD pathway have been extensively investigated, the SD pathway is much less understood. Here we identified a critical transcription factor called bHLH93 (basic Helix-Loop-Helix 93) that is essential to induce flowering specifically under SD conditions in Arabidopsis. bhlh93 mutants do not flower from primary meristem under SD conditions, but flowers similar to wild type under LD conditions. The late flowering phenotype is rescued by exogenous application of GA, suggesting that bHLH93 acts upstream of GA pathway to promote flowering. Double mutant studies showed that bhlh93 is epistatic to phyB and soc1 genes under SD conditions. bHLH93 is expressed at the meristematic regions and its expression peaks at 8 hours after dawn under SD conditions. As expected, the bHLH93 is localized in the nucleus. Taken together, these data suggest that bHLH93 is a key transcription factor necessary for Arabidopsis thaliana to evolve as a facultative plant. Stratified Col-0 and bhlh93-1 mutants seeds in cold for 4 days. Transferred to Short Day (8h light and 16h dark) chamber and harvested samples after 10days. Tissue was harvested 0 and 4 hour after light was turned on.

ORGANISM(S): Arabidopsis thaliana

SUBMITTER: Enamul Huq

PROVIDER: E-GEOD-29786 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

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Role of bHLH93 in controlling flowering time in Arabidopsis

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