Highly Homologous RING domain 2（At5g43200）encodes a RING finger E3 ligase. According to publicaly available microarray analysis, this gene may be involved in salt stress response. To study the fuction of At5g43200 in response to salt stress, the T-DNA insertion mutant athhr2 was obtained, and 3 homozugous complementary transgenic lines athhr2/ATHHR2 were obtained. The mutants, complementary transgenic lines and wild-type of Arabidopsis were used for salt stress experiment. Germination Rates and resistance - related physiological indexes of all the plants were measured, including proline content and chlorophyll content. Under salt treatment, the germination rate, relative proline content and chlorophyll content in deficient mutants are lower than the wild-type, and those of complementary transgenic plants are all higher than the wild-type. These results suggested that AtHHR2 gene played a positive regulatory role in Arabidopsis thaliana response to salt stress, our study laid foundation for further analysis on the gene’s function．
