The 30th International Conference on Arabidopsis Research (ICAR 2019)

430 / 2019-01-28 16:26:19

An AtAGO2-interacting protein MUG13.4 positively regulates salt tolerance in Arabidopsis

AtAGO2, MUG13.4, salt stress, Arabidopsis thaliana

Plenary track > Abiotic Stress

Salt stress is a worldwide threat to plant growth and development. AtAGO2 played a key role in salt stress, however, its molecular mechanism remains unclear. Here, we performed yeast two-hybrid and found a R3H-domain containing protein, designated MUG13.4, interacted with AtAGO2. Further bimolecular fluorescence complement (BiFC), glutathione (GST) pull-down, and coimmunoprecipitation (CoIP) assays confirmed MUG13.4 interacted with AtAGO2, and this process was dependent on RNA molecule. MUG13.4 have the similar expression pattern with AtAGO2, which were both almostly expressed in dry seeds and roots, and exogenous abscisic acid (ABA) and salt stress could induce MUG13.4/AtAGO2 expression at transcript level. Phenotypic analysis revealed the root growth of loss-of-function mug13.4 mutant was severely inhibited exposed to salt stress, however, during germination, mug13.4 mutant was hyposensitive to ABA while overexpression of MUG13.4 plants was hypersensitive to ABA. Moreover, mug13.4 mutant conferred hypersensitive to salt stress while overexpression of MUG13.4 was more tolerant to salt stress compared with that in wild type (WT) plants in seed germination and the growth of post-germination. Several salinity responsive genes (DREB2A, NCED3, SRM1 and RD29A) were regulated by MUG13.4. Taken together, we summary that MUG13.4 interacts with AtAGO2 and functions in salinity-stress response in Arabidopsis thaliana.