The Effect Of PSC1 Gene On The Growth Of Root And Root Hair Regulated By Auxin In Arabidopsis

Auxin and brassinosteroid play essential roles in plant development and they interact. In our previous studies, an arabidopsis brassinosteroid biosynthesis mutants pscl was screened, and we found brassinosteroid was involved in the signal transduction of jasminate. Moreover, the signal transduction of both brassinosteroid and auxin are through the SCF ubiquitin degradation pathway. In this paper, pscl and other mutants were used to further investigate the relationship between brassinosteroid and auxin, it was studied in two aspects:1,Effect of brassinosteroid on the role of auxin to arabidopsis root growthBy analyzing the response of arabidopsis seedlings root growth on auxin, we found that (1) pscl mutant showed hypersensitive to auxin; (2) Brassinosteroid partially suppressed seedlings in auxin inhibition of root growth; (3) pscl mutant partially restored the response of tir 1-1 mutant in auxin. These results indicated that Brassinosteroid negative regulated the auxin signal transduction.2,Effect of brassinosteroid on the role of auxin to arabidopsis root hair growthStereomicroscope was employed to observing the phenotype of root hair, we found that (1)pscl mutants can improve sensitivity of root hair growth to auxin; (2) Brassinosteroid can partially suppressed the promotion of Auxin to root hair growth; (3) pscl mutant partially inhibited the insenitivity of root hair growth of tir 1-1 mutant to auxin. These results further indicated that Brassinosteroid negative regulated the auxin signal transduction.