| 1. Isolation of plant disease resistance genes (R genes) had great significance for plant resisitance breeding and the study on disease resistance mechanism. Recent study had showed that resistance genes had common conserved domains, such as nucleotide bingding site(NBS), lecuine-rich repeats(LRR), leucine zipper(LZ), serine-threonine kinase(STK) and toll-interleukin-1 receptor(TIR).Primers designed based on the conserved domains,many resistance gene analogs (RGA) had been amplified by PCR.Then the RGAs were used as probes to check up the DNA library or cDNA library,and the candidate clones of resistance gene were eventually obtainded.This Paper reviewed the structure characters of R genes,the application and strategy of homology-based candidate gene method.In this study, Based on the reported primer with NBS-LRR domain , the PCR product of 11 kinds of bamboo of Phyllostachys are cloned. The results are as follows through the Biological Informatics analized.â‘ RGAs in different kinds of Bamboo are in high homologous sequences. Except Phyllostachys shuchengenis, Phyllostachys dulcis and Phyllostachys cv.Huangwenzhu could be regarded as one kind of RGA, the others could be regarded as another one. RGA is of great difference between Phyllostachys shuchengenis and others, their homologous is only 88%,the same RGA with NBS-LRR have such great difference in the same Phyllostachys ,that is diversities of RGAs in Phyllostachys is very obvious.â‘¡Compared with Arabidopsis thaliana, RGAs in different Bamboo is with partial homologous, but they are homologous with Arabidopsis thaliana RPS2, especially in NBS-LRR domain.Compared them with the known R gene,such as L6, N, RPS2, ,we found RGAs cloned are different from the known ones,and the ratio is 40%,34%,32% separately, in another word, they exsist divisities.â‘¢11 RGAs cloned with NBS-LRR is obviously different from other genes, their functions in disease resistance need more study. |
PDF Full Text Request