Transposon-based high sequence diversity in Avr-Pita alleles increases the potential for pathogenicity of Magnaporthe oryzae populations

Abstract

Magnaporthe oryzae causes rice blast that is one of the most devastating diseases of rice worldwide. Highly variable nature of this fungus has evolved itself against major resistance genes in newly released rice varieties. Understanding the population structure of this fungus is essential for proper utilization of the rice blast resistance genes in rice crop plants. In the present study, we analyzed 133 isolates of M. oryzae from ten countries to find the allelic variation of Avr-Pita gene that is triggering Pita-mediated resistance in rice plant. The diversity analysis of these alleles showed higher level of nucleotide variation in the coding regions than the noncoding regions. Evolutionary analysis of these alleles indicates that Avr-Pita gene is under purifying selection to favor its major alleles in 133 isolates analyzed in this study. We hypothesize that the selection of favorable Avr-Pita allele in these isolates may occur through a genetic mechanism known as recurrent selective sweeps. A total of 22 functional Avr-Pita protein variants were identified in this study. Insertion of Pot3 transposable element into the promoter of Avr-Pita gene was identified in virulent isolates and was suggested that mobility of repeat elements in avirulence genes of M. oryzae seems to help in emergence of new virulent types of the pathogen. Allele-specific markers developed in this study will be helpful to identify a particular type of Avr-Pita allele from M. oryzae population which can form the basis for the deployment of Pita gene in different epidemiological regions.

Genome-wide association study of blast resistance in indica rice

“…Of these associated loci, some were overlapped or coincided with previously identified genes and QTLs [ 27 - 29 ]. If the range was extended to 300 kb (±150 kb), more known genes might have been detected, such as Pita [ 7 , 45 , 46 ]. In addition, we detected newly associated loci that were characterized by the presence of R genes.…”

Synthesis of Polyacrylate‐Based Chalcone Containing Different Donor Moieties and Studies on their Optical, Electrochemical, and Thermal Properties

“…Pi-conjugated organic fluorophores containing donor acceptor groups that are separated by an ethenyl or keto-vinyl bridge, exhibiting the phenomenon of dual fluorescence are of special interest because the material properties can be tuned and tailored by structural modification for their potential applications in molecular electronics, dye sensitized solar cells (DSSCs) and other optical devices. 8,9 In current, PV technologies are focused in the application of metal-free organic polymers; since the metal-free organic polymers possess the common system of donor-p-bridge-acceptor (D-p-A) as alternative sensitizers provide several advantages including low cost, light weight and good flexibility, 10 which have been employed to design various polymers according to individual demands for specific applications. 11,12 More importantly, soluble semiconducting polymeric materials can be readily processed and easily printed, removing the conventional photolithography for patterning, which is a critical issue for the realization of large-scale roll-to-roll processing of printed electronics.…”

Genome-Wide Analysis of Genetic Variations and the Detection of Rich Variants of NBS-LRR Encoding Genes in Common Wild Rice Lines

“…The high percentage of SV/CNV variant TEs is reported before in mouse genome (Quinlan et al 2010 ). The transposons played a key regulatory role in plant stress response (Negi et al 2016 ), which are responsible for gene expression change and phenotypic differentiations (Singh et al 2014 ; Dhadi et al 2015 ; Tan et al 2017 ). These SV/CNV variant TEs may cause a dramatic genome rearrangement and have a strong influence on gene expression and resistance level of these three materials.…”