MOLECULAR DIVERSITY OF NBS-LRR DISEASE RESISTANCE GENE (RGAs) IN VIETNAMESE RICE VARIETIES
T. D. DUONG
Deparment of Genetic Engineering, Institute of Agricultural Genetic, Hanoi, Vietnam
K. H. TRUNG
Deparment of Genetic Engineering, Institute of Agricultural Genetic, Hanoi, Vietnam
N. T. KHOA
Deparment of Genetic Engineering, Institute of Agricultural Genetic, Hanoi, Vietnam
T. D. VUONG
Deparment of Genetic Engineering, Institute of Agricultural Genetic, Hanoi, Vietnam
C. T. HUONG
Deparment of Genetic Engineering, Institute of Agricultural Genetic, Hanoi, Vietnam
D. M. TRUNG
Biomedical & Pharmaceutical Applied Research Center, Vietnam Military Medical University, Hanoi, Vietnam
F. C. CHEN
Plant Industry Department of National Pingtung, University of Science and Technology, Taiwan
L. T. NGHIA
Department of Biotechnology, Plant Resources Center, Hanoi, Vietnam
N. N. TOAN
Department of Biology, Hanoi Pedagogical University No 2, Vietnam
T. D. KHANH *
Deparment of Genetic Engineering, Institute of Agricultural Genetic, Hanoi, Vietnam
*Author to whom correspondence should be addressed.
Abstract
Genes conferring resistance to major classes of plant pathogens including bacteria, virus, fungal and nematode, have been isolated from the different plant species. The most common class of plant disease resistance genes cloned so far belongs to the nucleotide binding sites-leucine rich repeat (NBS-LRR) disease resistance. Using the polymerase chain reaction (PCR) with degenerate oligonucleotide primers, a 500 bp band from the rice genomic DNA was amplified. The fragments from thirty-five different rice varieties from Vietnam were cloned and showed the similarity with known NBS-LRR resistance genes. Comparison of the deduced amino acid sequences of the resistance gene analogues (RGAs) sequences with products of known resistance genes revealed that the RGAs were as similar to each other as they were to resistance genes from other species (42% with I2-C2 of tomato and 38% with Xa1 of Oryzae sativa). Our results have indicated that it is possible to use sequence homology from the conserved motif of known resistance genes (R) to amplify candidate resistance gene from rice germplasm.
Keywords: Nucleotide-binding sites-leucine rich repeat (NBS-LRR), resistance gene analogues (RGAs), resistance gene (R), homology, degenerate oligonucleotides