Molecular Cloning Of Transparent Testal (BnTT1) Gene Family Eoconding WIP-Zinc Finger Proteins And Differential Expression Between Yellow-and Black-Seeded Lines Of Brassica Napus

Oilseed rape (Brassica napus L.) is an important oil crop in China. Yellow-seeded rapeseed has thinner seed coat, and contains less seed coat pigment and crude fiber, thus shows outstanding quality advantages over black-seeded cultivars. But in B. napus, yellow seed genotype is quite scarce, the inheritance and phenotype of yellow seed trait is unstable, yellow seed cultivars are deficient and it is difficult to breed, and the fundamental study on yellow seed trait is quite lagged behind.Arabidopsis thaliana Transparent testa 1 (TT1, or AtTT1) gene encodes a WIP type C2H2 zinc finger protein, positively regulating cell development and pigment synthesis and deposition in seed coat. As for B. napus, which is also a Brassicaceae species as A. thaliana does, study on TT1 gene will help to elucidate the seed coat development and yellow seed trait formation. In this research, the full-length cDNAs and corresponding genomic sequences of 2 members of B. napus TT1 gene family (BnTT1) were isolated and analyzed, their expression patterns were characterized, and a antisense plant expression vector was constructed. The main results are as follows: 1. Cloning of the full-length cDNA and genomic sequences of 2 members of BnTT1 gene family from B. napusWe adopted special primers to carry RACE amplifications and obtained plentiful 5'and 3'cDNA ends. Then 2 full-length cDNAs and corresponding genomic sequences were amplified. They are named BnTT1-1 and BnTT1-2, with genomic lengths of 1919 bp and 1798 bp, respectively. They both contain 1 intron (873 bp and 785 bp respectively) and 2 exons.Southern blot hybridization indicated that maybe there are 3 members of BnTT1 gene family in B. napus. Thus, in addition to BnTT1-1 and BnTT1-2, there is at least 1 member need to be isolated.