InterPro domain: IPR001954

Gluten is the protein component of Triticum aestivum (Wheat) flour. It consists of numerous proteins, which are of 2 different types responsible for different physical properties of dough: the glutenins, which are primarily responsible for the elasticity, and the gliadins, which contribute to the extensibility. The glutenins themselves are of 2 different types, termed low and high [ 1 ] molecular weight subunits. The latter have unusual structures: a central region contains multiple tandem repeats of blocks of amino acids, forming a loose helix based on beta reverse turns, and is flanked by globular regions, which can be cross-linked by disulphide bonds. The result is an elastic network in which the elasticity may derive from the cross-linking, the helical structure, or a combination of these [ 2 ].

The gliadins are also of different types (e.g., alpha/beta or gamma) and, like the glutenins, contain repetitive sequences [ 3 ] that form loose helical structures, but are usually associated with more extensive non-repetitive regions, which are compact and globular [ 4 ].

This family also includes avenin-like proteins, which are considered atypical gluten constituents [ 5 ].

1. Nucleotide sequence of a gene from chromosome 1D of wheat encoding a HMW-glutenin subunit. Nucleic Acids Res. 13, 6833-46
2. Nucleotide sequences of the two high-molecular-weight glutenin genes from the D-genome of a hexaploid bread wheat, Triticum aestivum L. cv Cheyenne. Nucleic Acids Res. 17, 461-2
3. Evolution and heterogeneity of the alpha-/beta-type and gamma-type gliadin DNA sequences. J. Biol. Chem. 260, 8203-13
4. Structure of wheat gamma-gliadin genes. Gene 43, 221-9
5. Genetic characterization of cysteine-rich type-b avenin-like protein coding genes in common wheat. Sci Rep 6, 30692