Cloning And Expression Analysis Of Floral Determination Homologous Gene BmID1in Bambusa Multiplex

Bamboo usually dies after flowering，which have a very bad affect on the management of bambooforest. The research of the bamboo flowering is very important to sustainable operation of bambooforest. RID1/OsID1/Ehd2and ZmID1acts as a master switch from the vegetable phase toreproductive phase in rice. It helps understand the mechanism of the floral transition in bamboo plant.Based on the research of RID1/OsID1/Ehd2and ZmID1in rice and maize，the RID1orthologue wasisolated through homologous cloning in Bambusa multiplex. The feature of expression level was testedby RT-PCR and prokaryotic expression in vitro. We found that the character of autonomous pathwayabout flowering was existed in the process of flowering in B. multiplex through field observation andreference report. The results are as follows:1、The RID1orthologue was isolated form B. multiplex and named BmID1. The full-lengthgenome DNA of BmID1is2457bp and the full-length cDNA is1182bp，encoding an393aminoacid. The structure of BmID1is comprised of four exons and three introns. BmIDI is atranscription and contains a putative nuclear location signal, four zinc finger motifs andconserved TRDFLG motif. Bioinformatics analysis showed that the homology of amino acidsequence，physicochemical property and conservative motifs of BmID1were similiar to OsID1and ZmID1. MSATALLQK motif was lacked in BmID1, OsID1and ZmID1.2、RT-PCR analysis showed that the expression of BmID1was weakly through the one day andhigher expression in16:00, and that BmID1was expressed very low in tested tissues exceptmature leaves. In comparison, the expression level in the various tissue was in the order, youngleaf>root>stem>flower>shoot.3、BmID1promoter sequence analysis found17response elements including light-response, GAresponse and a68bp-length tandem repeat sequence which might transcript small RNAs andparticipate in epigenetic modification.4、Two prokaryotic expression vectors were constructed and induced under different temperature.SDS-PAGE analysis showed that the molecular weight of the induced protein was about25kDand45kD, the approximate to that of the predicted weight.