CHARACTERIZATION AND TISSUE-DIFFERENTIAL EXPRESSION OF FAD2 GENES IN BRASSICA NAPUS

In this study, genome DNA and RNAof fad2 genes from three types of oleic acid content from B. napus were isolated by PCR amplification, respectively, the results showed that not only had nucleotides sequences little differences from three types of oleic acid content B. napus, but also that of genome DNA and cDNA had still little differences from B. napus as far as specific one type of rape. Different genotypes fad2-I and fad2-II could be easily distinguished by sequence analysis of the cDNAs in G type and CK type except in D type. By analysis on cDNAs, specific differences could be found in three types of rape when compared with the sequence from Genebank. Conserved domains prediction and phylogenetic analysis showed that both six transmembrane domains and three H boxes could be found in FAD2 protein from three types of oleic acid content B. napus, respectively. BnFAD2-I and BnFAD2-1I belonged to different classes and class I could be divided into two kinds. By QPCR, expression pattern of fad2 gene in different tissues showed that simple division of fad2-land fad2-II was not apply to all oleic acid content B. napus. By southern blot, there were differences in copy numbers of fad2 genes on different oleic acid content B. napus.