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The impact of the genes BBX32 and HY5 on the high light - responsive transcriptome of Arabidopsis thaliana

ABSTRACT: Exposure of mature fully expanded leaves of Arabidopsis to a 7.5 fold increased light intensity above growth light conditions (high light; HL) tirggers stress defensive responses but also initiates cellular processes, that if such conditions persist, can lead to increased photosynthetic capacity. This process is called dynamic acclimation. By using variational Bayesian state space modelling on eariler GEO deposited time series HL data (see GSE78251) a gene regulatory network of (co) transcription factor genes was inferred. The most connected gene in this network is BBX32, which was subequently shown to be a negative regulator of dynamic acclimation. Also present in the inferred network is HY5, which is known from studies on seedling photomorphogenesis to be antagonistic in its action to BBX32. Subsequently, it was demonstrated that HY5 is indeed a positive regulator of dynamic acclimation. This RNAseq-based study seeks to provide gene expression data that will help to link the immediate impact of these genes on the HL transcriptome to the longer term (several days) physiological manifestation of dynamic acclimation.

ORGANISM(S): Arabidopsis thaliana

PROVIDER: GSE158898 | GEO | 2021/04/01

REPOSITORIES: GEO

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Temporal analysis of physiological and transcriptome responses during high light exposure that lead to dynamic acclimation in Arabidopsis

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