The Function Study Of A SAUR Gene In Arabidopsis

Auxin is the first plant hormone discovered in experimental biology, regulates a host of plant developmental and physiological processes, including embryogenesis, vascular differentiation, organogenesis, tropic growth, and root architecture. Auxin functions, at least in part, by regulating a set of early auxin response genes: Aux/IAAs, GH3s and Small auxin-up RNAs (SAURs). After auxin treatment, these genes accumulate rapidly. There are 72 SAUR genes in Arabidopsis. However, the function of SA URs remains obscure. It is significant to make sure the function of SAURs in plant growth.In this study, we used molecular biology and transgene technology to reveal the function of atSAUR41(Atlg16510). We constructed a SAUR41 over-expression vector and a fusion protein vector thtough the Gateway system. Through observation, we found that transgene plants over-expressing the SAUR41 gene resulted in richer roots, taproot with weaker gravitropism, more lateral roots, larger cotyledon, and longer hypocotyl compared with wild-type plants. It suggests that the SAUR41 gene maybe affect auxin transport in root tip and refer to BR; The GFP of the fusion protein transgenic plants was observed in a fluorescent microscope, expressed in cytoplasm. To figure out what SAUR really does to affect auxin, we constructed a series vectors that different promoters drive SAUR41 expression. By the comparation of the Auxin distribution and phenotype statistics results in transgene lines, we hypothesized that the SAUR acts as a regulator of auxin transport, but the mechanism still need to be furthur studied.