Molecular characterization and phylogenetic analysis of Wx genes from three Taeniatherum diploid species

Abstract

In wheat seeds, starch synthase I or Waxy protein is the enzyme involved in amylose synthesis. The gene encoding this enzyme is Wx and in this study, eight novel Wx alleles were identified in three diploid Taeniatherum species. The variability of these alleles was evaluated and their nucleotide sequences were compared with those of homologous alleles from wheat. Two types of Taeniatherum Wx alleles were detected in the three diploid species Ta. caputmedusae, Ta. asperum, and Ta. crinitum. A phylogenetic analysis indicated that Taeniatherum Wx alleles were more closely related to Wx alleles from Aegilops species with C, D, M, and U genomes than to Wx alleles of other species. These alleles represent a potential genetic resource that may be useful in wheat breeding programs.

Waxy Gene-Orthologs in Wheat × Thinopyrum Amphidiploids

“…searsii, Triticum monococcum ssp. monococcum, T. urartu and Taeniatherum revealed amino acid substitutions, which can affect the GBSSI protein activity [27,28,37]. In Motif VII-VIII in Th.…”

“…In accordance with previous publications on the production and characterization of the nucleotide sequences of the Wx genes in Triticeae [27,37,38], we designated the obtained sequences in the following manner: Wx-J b 1 for Th. bessarabicum (2x = 2n = 14, J b J b ), Wx-Ps stip 1 for P. stipifolia (2x = 2n = 28, St 1 St 1 St 2 St 2 ), Wx-Th inter 1 for Th.…”

“…et Schult. have been published [37,38]. Studies on the Wx gene in the tertiary gene pool, such as Elymus, Thinopyrum, Leymus, Pseudoreogneria and other grasses, are limited and, in general, have partial sequences, and are aimed at phylogenetic studies rather than discovering complete gene sequence [39,40].…”