Cloning And Expression Of BvCIGR2 Gene Of Bambusa Ventricosa McClure And Expression In Arabidopsis Thaliana

As a kind of hormones with wide range of physiological functions in plants, Gibberellins (Gibberellic Acid, GA) involves in many complex processes of regulating plant growth and development, such as seed germination, stem elongation, flower development and so on. Gibberellin biosynthesis pathway has now been clearly studied, and related genes has been cloned. Gibberellin signal transduction in Arabidopsis, rice and other model plants has made substantial progress and the mode of signal transduction has been basically established. A number of signal transduction pathways of the intermediate components have been identified, in which GRAS protein family can sense GA signals and plays an important role in the GA signal transduction. At present, a number of GRAS family members have been cloned, such as two GA-signal response factors, OsCIGR1 and OsCIGR2 in rice.The article was aimed to explore regulation function of GA in shoot distortion of baby Bambusa ventricosa. Using primers designed based on the cloned CIGR2 sequences and with the method of RACE, a homologous gene of OsCIGR2 from baby shoots of Bambusa ventricosa McClure was first cloned, and the reverse transcription production with a complete full-length cDNA coding region, named as BvCIGR2. Its tissue-specific expression was studied using RT-PCR, and vector was further built to translate into Arabidopsis thaliana to study gene functions, and achieved the following results:1) The full length cloned cDNA of BvCIGR2 contains 2143 bp, and its ORF encoding 545 amino acids. Bioinformatics analysis indicated that BvCIGR2 contained the conserved domain of the GRAS protein family. Homology of its amino acid sequence with the rice OsCIGR2 showed the highest similarity of 87%, followed by corn ZmCIGR2, similarity of 80%, and the postulated RcCIGR2, similarity of 63%.2) RT-PCR results showed that, BvCIGR2 was expressed in the leaves, leaf buds, internodes, bamboo shoots and roots, with the highest expression abundance in the upper end of internode, followed by the mid-internode, then followed by the lower end of internode and the lowest in the shoots.3) The plant expression vector pCAMBIA1304++BvCIGR2 was constructed, and transferred into Agrobacterium tumefaciens GV3101. The research of BvCIGR2 gene translating into wild-type Arabidopsis was completed, and the positive seedlings were initially screened out.BvCIGR2 gene expression of the organization was studied in order to explore its regulation of the shape of stalk in Bambusa ventricosa McClure and lay the foundation of shaped variation. By screening out the positive seedlings can laid certain basement for further screening and research on effect of BvCIGR2 on the morphogenesis of Arabidopsis.Furthermore, it may also give some referrence on how BvCIGR2 regulates the foundation of the shape building of bamboo stalk in Bambusa ventricosa McClure.