Functional Analysis Of Rice OsDUF1336.2 In Response To Drought Stress

Abiotic stresses,such as drought,have a great impact on the normal growth,development and yield in rice.Domains of unknown function protein families(DUFs)exist in plants widely and play important roles in many biological processes,such as growth,development and abiotic stresses.OsDUF1336.2 is a drought responsive gene by rice gene microarray.In this study,the drought tolerance functional analysis of OsDUF1336.2 gene was analyzed,and the main results were as follows:(1)The OsDUF1336.2 gene is located on chromosome 3,with an open reading frame of 1614 bp and encoding 538 amino acids.There are multiple cis acting elements related to stress response in the promoter region.(2)The gene express in rice seeds,roots,stems,leaves,sheaths,and inflorescences,with the highest expression level in seeds.The gene expression is upregulated under drought stress conditions.(3)The OsDUF1336.2-GFP fusion protein is located on the cell membrane.(4)Under 20% PEG and sand culture drought conditions,the survival rate of overexpressed rice seedlings increased,while the survival rate of gene knockout rice seedlings decreased.(5)Under drought stress conditions,the content of malondialdehyde(MDA)significantly decreased in overexpressed rice seedlings and increased in gene knockout rice seedlings.The activities of active oxygen scavenging enzymes,such as superoxide dismutase(SOD)and peroxidase(POD)increased in overexpression rice seedlings,while the activities of SOD and POD decreased in gene knockout rice seedlings.(6)Overexpression increases their sensitivity to exogenous abscisic acid(ABA)in rice seedlings,while gene knockout reduces their sensitivity to exogenous ABA.Under drought conditions,the expression level of the ABA synthesis related gene OsNCDE1 increased,while the expression level of the ABA degradation related gene OsABA8OX2 decreased in overexpressed rice seedlings.However,the expression level of OsNCDE1 decreases and the expression level of OsABA8OX2 increases in gene knockout rice seedlings.In addition,the expression levels of ABA downstream signal transduction related genes OsSNAC1 and OsDREB2 A were upregulated in overexpressed rice seedlings,while downregulated in gene knockout rice seedlings.