Primary Analysis Of The Function Of BdTRN1

The material transfer between nuclear and cytoplasm is essential to all cell activities.Therefore studies on nucleocytoplasmic transport processes and their mechanisms have great scientific significance.TRN1(transportin 1)mediates the nuclear import of many cargo proteins from cytoplasm.Alternations on its level and activity affect the growth and development processes of the whole organism.To date,the function of of transportin protein in Brachypodium distachyon has not been characterized.In this work,we cloned BdTRN1 gene from Brachypodium distachyon and established an embryonic callus transformation system,and succeeded in generating of BdTRN1 overexpression lines.We also identified a T-DNA insertion mutant of BdTRN1 and mapped its insertion site.This mutant exhibited similar phenotypes with Arabidopsis sic1 mutant.Bioinformatic analysis showed that TRN1 is a conserved protein,and our complementation experiment of Arabidopsis sicl mutant with BdTRN1 confirmed this view as well.In addition,BdTRN1 protein localized in both nuclear and cytoplasm,which is similar to AtTRN1.Using yeast two hybridization,we identified two Brachypodium distachyon proteins BdRNP1 and BdGRP7 who interact with BdTRN1,andBdRNP1 also interacted with AtTRN1,However,we found no interaction between AtTRN1 and BdGRP7,suggested the difference between the two species.This work reported transportin protein of Brachypodium distachyon for the first time,and provides primary evidences of BdTRNl may have similar functions to other plant homologues,despite they may have distinct cargoes.All these fundamental results will be useful to further depth investigations on BdTRN1 and nucleocytoplasmic transport in Brachypodium distachyon.