Knowledge Center Catalog

Molecular characterization of two novel null waxy alleles in Mexican bread wheat landraces

Guzman, C.

Molecular characterization of two novel null waxy alleles in Mexican bread wheat landraces - London (United Kingdom) : Elsevier, 2015.

Peer review

Starch is composed of two glucose polymers: amylose, formed by long linear chains, and amylopectin, which is larger and highly branched. The ratio between the two polymers (usually 22-35% amylose, 68-75% amylopectin) affects the starch properties, thereby determining different aspects of wheat quality. Waxy protein, which is the sole enzyme responsible for amylose synthesis, showed polymorphism in a collection of one hundred and three Mexican landraces, including null alleles at Wx-A1 and Wx-B1 loci, respectively. Molecular characterization of these alleles showed that the null Wx-A1 allele presented in only one accession was novel (Wx-A1o) and involved a deletion spanning the three and a half last exons of the gene. Some of the accessions lacking the Wx-B1 protein contained the common allele Wx-B1b (12.6%) (deletion of approximately 67 kb), while four others (3.8%) possessed the novel Wx-B1l, characterized by the deletion of one cytosine in the second exon of the gene and leading to a change in the ORF. This novel allele is particularly interesting because the absence of the Wx-B1 protein in this case was not associated with the lack of the other genes included in the approximately 67 kb region lost with the common null allele Wx-B1b.


Text in english

https://doi.org/10.1016/j.jcs.2014.11.003


Wheat
Food quality
Alleles
Landraces

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