RESUMO
OsRacD is a critical molecular switch involved in photoperiod fertility conversion of photoperiod sensitive genic male sterile rice.Taking OsRacD as bait,a new rice myosin heavy chain partial cDNA was isolated from the rice panicle by yeast two-hybrid,and designated OsMY1.The interaction between OsMY1 and OsRacD had been testified by yeast two-hybrid and pull down assay,it showed that OsMY1 could bind with OsRacD,suggested that OsMY1 maybe the target of OsRacD.The important evidence for further study on the functional relationship between OsMY1 and OsRacD in vivo are also provided.
RESUMO
OsRacD belonging to rice Rho family of the small GTP binding proteins,is a pivotal gene involved in rice photoperiod fertility conversion of photoperiod sensitive genic male sterile rice,which influences rice fertility via controlling the pollen tube growth.T20N site-directed mutation was introduced into its highly conserved G1 motif by PCR-mediated method to mimic its GDP-binding state based on the sequences alignment and conserved domains analysis.The prokaryotic expression vector of OsRacD and T20N-OsRacD were constructed,and the His6 tag fused proteins were expressed and purified from E.coli.After identified by Western blot,the GTP hydrolysis activities were detected.The results showed that the GTPase activities of T20N-OsRacD were significantly reduced comparing with that of OsRacD,suggested that OsRacD and T20N-OsRacD have different biochemical characteristics.