Molecular Cloning, Expression Profile And Function Analysis Of MADS-box Genes In Cotton

Cotton is the important economic crop in China. Early maturity is one of the characteristics of cotton, while the flowering time determines the maturity of cotton. MADS-box genes are important transcription factors. They are found in animals, plants and fungi. MADS-box transcription factors have a 56 to 58 amino acids highly conserved region known as the MADS-box domain, the genes with the domain of MADS-box are genes belonging to MADS-box gene family. MADS-box genes control diverse developmental processes in flowering plants ranging from root to flower and fruit development, especially control the processes of the transition from vegetative to reproductive development and establishment of floral organ identity. Except for the Arabidopsis A-function gene APETALA2 (AP2) and homologs, all ABCDE genes are members of the MADS-box gene family and encode putative transcription factors. So in this study, flowering genes MADS-box gene family as the object, the short season cotton CCRI36 for the material, using fragment assembly and PCR amplification cloning MADS-box genes in cotton. By QRT-PCR, the expression of these genes was done. GhMADS12 and GhMADS13 genes transgenic gene function validation tools for the study of early maturing cotton foundation. The study's main findings are as follows:1. Based on NCBI and TIGR EST databases, splicing through sequences and PCR amplification method combined total of cotton MADS-box genes 34.2. With Arabidopsis and grape MADS-box genes, the obtained MADS-box genes in cotton phylogeny that we have 10 sub-groups MADS-box gene in cotton. The evolutionary relationship between homologous was analyzed.3. Using quantitative PCR technique, the expression of MADS-box genes in CCRI36 in roots, stems, leaves, flowers, buds, ovules in the six parts was done. The expression of most MADS-box genes was low in the vegetative organs, high in reproductive organs.4. From the 34 MADS-box genes, we chose GhMADS12 and GhMADS13 for further study.(1) GhMADS12 gene belongs to PI subfamily, while the PI subfamily genes in the ABCDE model of floral organ development is the B functional genes; The expression of gene GhMADS12: there was no expression of GhMADS12 in vegetative organs, while abundantly expressed in reproductive organs, especially in petals and stamens; The transfer GhMADS12 tobacco plant was changed in petals and stamens, verified that the GhMADS12 gene may involved in the development of petals and stamens.(2) GhMADS13 gene belongs to AGL6 subfamily, AGL6 subfamily genes in floral organ development is the exercise of the C function; The expression of gene GhMADS13: there was no expression or low expression of GhMADS13 in vegetative organs, while abundantly expressed in reproductive organs, especially in stamens and carpels; The transfer GhMADS13 gene tobacco plants changed in stamens and carpels, verified that the function of GhMADS13 gene is play a role in the development of stamens and carpels.