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bioRxiv · 10.1101/2020.08.31.275271

F-box protein At1g08710 negatively regulates root length and imparts drought stress tolerance in Arabidopsis thaliana.

Abstract

Plants experience abiotic stresses throughout their life cycle and accordingly respond to tide over the unfavorable conditions. Drought or water deficit is one such condition to which plants respond in various ways including the ubiquitin proteasome system (UPS). Ubiquitin E3 ligases are a diverse family of protein complexes of which Skp1{square}Cullin{square}F{square}box (SCF) class mediate the ubiquitination and subsequent proteolytic turnover of proteins. F{square}box protein subunit plays crucial role in imparting specificity for selective degradation of target proteins. Here we report the function of Arabidopsis F-box protein At1g08710 in drought stress adaptation. As F-box protein is a constituent of SCF complex, here it is shown interacting with ASK1 and Cullin1. F-box protein localizes to both nucleus and membrane. F-box gene transcript accumulates highly in root and is altered in response to drought stress conditions. F-box protein interacts with a transcriptional co-activator protein ADA2b. F-box mutant plants displayed better growth under drought stress conditions compared to the wild type with a reduced accumulation of H2O2 and malondialdehyde (MDA). Drought responsive genes RD29A, RD22, ABI3 expression is also induced in F-box mutant plants. These results indicate F-box protein At1g08710 plays a role in drought stress adaptation in Arabidopsis thaliana. HighlightsO_LIF-box gene At1g08710 encodes a nuclear, membrane localized protein. C_LIO_LIF-box protein At1g08710 interacts with transcriptional co-activator protein ADA2b. C_LIO_LIF-box protein imparts drought stress tolerance by modulating H2O2 and MDA content. C_LIO_LIDrought response genes RD29A, RD22, ABI3 expression is induced in F-box mutant plants. C_LI

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BibTeXRIS

Rao, V., Vijaybhaskar, V.. 2020-09-01. F-box protein At1g08710 negatively regulates root length and imparts drought stress tolerance in Arabidopsis thaliana.. https://doi.org/10.1101/2020.08.31.275271

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