Comparative analysis of resistance gene analogues encoding NBS‐LRR domains in cotton

• Published in: Journal of the science of food and agriculture 2016-01, Vol.96 (2), p.530-538
• Main Authors: Khan, Abdul Manan, Khan, Asif Ali, Azhar, Muhammad Tehseen, Amrao, Luqman, Cheema, Hafiza Masooma Naseer
• Format: Article
• Language: English
• Subjects: abiotic stress; Amino Acid Sequence; artificial selection; Base Sequence; binding sites; Binding Sites - genetics; Comparative analysis; Cotton; diploidy; disease resistance; Disease Resistance - genetics; Diseases; Evolution; Evolution, Molecular; Gene sequencing; Genes; Genes, Plant - genetics; Genomes; Gossypium - genetics; Gossypium hirsutum; Gossypium spp; hybrids; leucine; Leucine - genetics; mutants; NBS-LRR domain; necrosis; Nucleotides - metabolism; Parents; Pathogens; Phylogeny; plant pathogens; Repetitive Sequences, Nucleic Acid; resistance gene analogues; Selection, Genetic; Sequence Homology; Sequence Homology, Amino Acid; Species Specificity; Stress response; tetraploidy; wild relatives
• ISSN: 0022-5142; 1097-0010
• DOI: 10.1002/jsfa.7120

BACKGROUND: Plant production is severely affected by biotic and abiotic stresses R‐genes exhibit resistance against a range of diseases and pathogens in plants. The nucleotide binding site and leucine rich repeat (NBS‐LRR) class of R‐genes is the most comprehensively studied in terms of sequence evolution and genome distribution. The differential response for resistance against biotic and abiotic stress has been observed in cultivated and wild relatives of the genus Gossypium. RESULTS: Efforts have been made to address the recent evolution of NBS‐LRR sequences within Gossypium hirsutum and resistance gene analogue (RGA) sequences derived from G. arboreum and G. raimondii. The % identity and phylogenetic analysis of NBS‐LRR‐encoded RGAs from tetraploid New World cotton and its diploid ancestors G. raimondii and G. arboreum suggest that the evolution of NBS‐LRR‐encoding sequences in G. hirsutum occurred by gradual accumulation of mutants that led to positive selection and a slow rate of divergence within distinct R‐gene families. CONCLUSION: The allotetraploid genome of cotton, after separating from its diploid parents, experienced polyploidisation, natural and artificial selection, hybrid necrosis, duplication and recombination which became the reason to shed off and evolve new genes for its survival. These driving forces influenced the development of genomic architecture that make it susceptible to diseases and pathogens as compared to donor parents. © 2015 Society of Chemical Industry