The Functional Study Of GADD45A Family In The ABA Response In Arabidopsis Thaliana

Abiotic stress,including high temperature,freezing,drought,salinity and UV are the main constraints for growth and development.As a sessile organism,plant has evolved an intricate molecular mechanism to cope with ever-changing environment.Abscisic acid(ABA)is an important phytohormone and regulates plant growth and development such as germination,seed dormancy,transition from vegetative to reproductive phase and abiotic stress tolerance.In mammals,GADD45 family proteins working as an adaptor can interact with many proteins and are involved in different biological processes including DNA demethylation and DNA repair.However,the exact function of GADD45 A family has not been reported in plants.By using homology search,we identified two GADD45 A family members in Arabidopsis,GADD45A1 and GADD45A2.We want to know if GADD45 family is involved in ABA response.The main conclusions of this study are as follows:(1)GADD45A1 and GADD45A2 localize to nucleus;(2)GADD45A1 and GADD45A2 can express in flower,root,leaf,cotyledon and silique;(3)We generated GADD45A1-and GADD45A2-overexpression-transgenic plants and observed they displayed ABA-hyposensitive phenotypes;(4)By taking advantages of genome-wide RNA-sequencing analysis,we found that different biological gene ontologies(GO)including abiotic stress,hormone stimulation,transcriptional regulation,and ABA response are enriched in GADD45A1 OX and GADD45A2 OX.Based on these results,we propose that GADD45A1 and GADD45A2 took part in the ABA-responsive gene expression.