Genome wide identification of nucleotide-binding site leucine-rich repeat (NBS-LRR) gene encoding regions in Solanum lycopersicum resistant to environmental pathogens by computational methods

Aim: The nucleotide binding site leucine rich repeat (NBS-LRR) genes are responsive to pathogen strike in plants. This study focused on identifying the loci specific NBS-LRR gene encoding regions in tomato at whole genome level. Methodology: Major computational challenges in analyzing large genomic data using existing analytical tools were limited by the amount of memory used for reading large data. In this study, a specific algorithm was developed to identify a signature pattern associated with stress tolerant coding regions using stream readers for reading whole tomato genome, chromosome wise, to locate NBS-LRR coding sequences. Results: The computer program reads chromosome wise data and extracts the potential stress tolerant coding regions. It was found that more than 300 disease resistance protein coding regions were found across all chromosome, specifically in chromosome 12 more NBS-LRR concentration were found and their respective locus were identified. Interpretation: The identified disease resistance protein coding regions, specifically the NBS-LRR coding regions and their loci can be useful for plant breeders to select parental lines for developing plants tolerant to disease and pest invasion

Cloning and analysis of a NBS-LRR disease resistance gene candidate PnAG1 from peanut (Arachis hypogaea L. )

Background: Based on the conserved sequences of a known NBS resistance gene, a pair of degenerate primers was designed to amplify the NBS-LRR resistance gene from peanut using PCR and RACE methods. Results: Analyzing the amino acid sequence by BLAST on NCBI, which was deduced from the 1088bp-long gene named PnAG1-2, showed that it had a certain homology with some resistance proteins, among which Arachis cardenasii resistance protein gene had the highest homology (66 percent). Relative quantification PCR analysis indicated that PnAG1-2 gene expresses more in J11 (an A. flavus-resistant variety) than in JH1012 (an A. flavus-susceptible variety) when the harvest time was coming. Conclusions: In this study, the NBS-LRR resistance sequence was successfully cloned from peanut and prokaryotic expression was done on the gene, which provided a foundation for cultivating anti-A. flavus peanut varieties.