ANALYSIS OF CODON USE FEATURES OF PLANT DISEASE RESISTANCE GENE

Compared to the whole genome,plant disease resistance genes( R genes) are highly diverse and evolved rapidly,and their mechanism of action is complex. The study of Resistance genes has been a hot spot area in Genetics and pathology. In this study,CodonW was used to analyze codon usages of 42 R genes from different plants. The results showed that the codons ending with A / T,especially T,were frequently used and GC content was lower than AT content in most of R genes. Relative synonymous codon usage( RSCU) analyses showed that28codons were preferable in the codons of coding DNA sequences( CDS) of R genes. Both cluster trees based on the relative RSCU and CDS of R gene could not reveal the evolutional relations of plant species. Howeve,they could indicate the similarity of genes with different functions and the differences between genes having same disease to some extent. Xa13,Xa21,Xa27 and Hm1 were significantly from most of R gene. For example,they use the codons ending with G / T more frequently than that ending with A / T. This study provided certain reference for the prediction of new R genes and the operation of gene engineering R genes.