Development of EMS-induced mutagenized groundnut population and discovery of point mutations in the ahFAD2 and Ara h 1 genes by TILLING
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Date
2021
Journal Title
Journal ISSN
Volume Title
Publisher
Japan Oil Chemists Society
Access Rights
info:eu-repo/semantics/openAccess
Abstract
Reducing allergenicity and increasing oleic content are important goals in groundnut breeding studies. Ara h 1 is a major allergen gene and Delta(12)-fatty-acid desaturase (FAD2) is responsible for converting oleic into linoleic acid. These genes have homoeologues with one copy in each subgenome, identified as Ara h 1.01, Ara h 1.02, ahFAD2A and ahFAD2B in tetraploid groundnut. To alter functional properties of these genes we have generated an Ethyl Methane Sulfonate (EMS) induced mutant population to be used in Targeting Induced Local Lesions in Genomes (TILLING) approach. Seeds were exposed to two EMS concentrations and the germination rates were calculated as 90.1% (1353 plants) for 0.4% and 60.4% (906 plants) for 1.2% EMS concentrations in the M1 generation. Among the 1541 M2 mutants, 768 were analyzed by TILLING using four homoeologous genes. Two heterozygous mutations were identified in the ahFAD2B and ahFAD2A gene regions from 1.2% and 0.4% EMS-treated populations, respectively. The mutation in ahFAD2B resulted in an amino acid change, which was serine to threonine predicted to be tolerated according to SIFT analysis. The other mutation causing amino acid change, glycine to aspartic acid was predicted to affect protein function in ahFAD2A. No mutations were detected in Ara h 1.01 and Ara h 1.02 for both EMS-treatments after sequencing. We estimated the overall mutation rate to be 1 mutation every 2139 kb. The mutation frequencies were also 1/317 kb for ahFAD2A in 0.4% EMS and 1/466 kb for ahFAD2B in 1.2% EMS treatments. The results demonstrated that TILLING is a powerful tool to interfere with gene function in crops and the mutagenized population developed in this study can be used as an efficient reverse genetics tool for groundnut improvement and functional genomics. © 2021 by Japan Oil Chemists’ Society.
Description
Keywords
Mutation, Oleic acid, Peanut, Reverse genetics, Allergens, Antigens, Plant, Arachis, Fatty Acid Desaturases, Genome, Plant, Linoleic Acid, Membrane Proteins, Oleic Acid, Peanut Hypersensitivity, Plant Proteins, Point Mutation, Reverse Genetics, Amino acids, Linoleic acid, Oilseeds, acyl coenzyme A desaturase, allergen, Ara h 1 protein, Arachis hypogaea, linoleic acid, membrane protein, oleic acid, plant antigen, plant protein, Allergen genes, Allergenicity, Amino-acids, Ara h 1, Desaturase, Ethyl methane sulphonate, Major allergens, Mutation, Point mutations, Reverse genetics, Arachis, genetics, immunology, metabolism, peanut allergy, plant genome, point mutation, procedures, reverse genetics, Genes
Journal or Series
Journal of Oleo Science
WoS Q Value
Scopus Q Value
Q3
Volume
70
Issue
11
