Targeting MAT Gene (LOC_Os11g15410) polymorphisms involved in tocopherol and tocotrienol conversions in rice
Andrea Irias Mata, Valery Conejo-López, Álvaro Azofeifa-Delgado, Andrea Holst and Luis Barboza-Barquero
Abstract: Accumulation of tocopherol and tocotrienol antioxidant compounds in rice seeds depends on enzymes involved in their biosynthetic pathways, including methionine adenosyltransferase (MAT). The aim of this study was to develop molecular markers for MAT gene LOC_Os11g15410 and evaluate associations between its polymorphisms and the accumulation of tocopherol and tocotrienol congeners in uncharacterized rice germplasm. Using high-resolution melting (HRM) analysis, we identified two consecutive SNPs (Chr11:8733700 bp and Chr11:8733701 bp) defining two haplotypes (AA and GG), and a novel 49-bp indel spanning from the second exon to the third intron. A panel comprising twelve rice samples and four Oryza sativa L. accessions was evaluated. The GG haplotype combined with the indel was associated with higher accumulation of δ and γ congeners, which are intermediates in the biosynthetic pathway. In contrast, the AA haplotype without the indel was associated with β and α congeners, which are end products of the MAT-mediated pathway.