Gliadin proteins in the developing wheat seed

Abstract

In extracts of developing seeds of wheat (Triticum aestivum L., cultivars Scout 66, Cheyenne, Nugaines and INIA 66R) examined by polyacrylamide gel electrophoresis, gliadin proteins appeared at 12-15 days post-anthesis with mobilities covering nearly the whole range found with mature seeds. Some differences among extractants [ 2~ dimethylformamide (DMF); 2111 urea; 60 % ethanol ; the aluminium lactate-lactic acid electrophoresis buffer, pH 3.21 in both intensity and occurrence of specific bands were observed. With immature seeds, 60% ethanol extracts produced a maximum number of bands and least background colour, but DMF and urea extracts showed bands from 12-to 15-day seeds at least as well as 60% ethanol extracts despite more background colour. Aluminium lactate buffer extracts occasionally yielded bands not found with other extractants, but gave poor extraction from immature seeds and relatively heavy background staining with mature seeds, especially in the w-gliadin (lowest mobility) region. A quantitative sodium dodecyl sulphate-electrophoresis procedurel was used to follow the formation of proteins in various molecular weight ranges (cv. Scout 66 only). At 12-18 days post-anthesis, synthesis of protein of molecular weight 30 000-37 000 accelerated, consistent with the onset and acceleration of formation of a-, /3-, and some y-gliadins. Protein in a band of 44 000 molecular weight formed in similar fashion. In other molecular weight ranges, gliadin bands could not be positively identified because of the complexity of the banding pattern of the total protein.

Hexaploid wild emmer wheat derivatives grown under New Zealand conditions 3. Influence of nitrogen fertilisation and stage of grain development on protein composition

“…By 28 days after anthesis these were replaced by gliadins, suggesting structural changes or dissociation had occurred. Mecham et al (1981) noticed similar bands and suggested that they may have resulted from the formation of protein -lipid comple?Ces .…”

“…Several reports have indicated that the entire range of gliadin proteins are present at or before 14 days after anthesis (Barlow et al 1974;Flint et al 1975;Mecham et al 1981;Terce-LaForgue & Pernollet 1982). However, other workers have concluded that only low molecular weight (LMW) gliadins are present at this stage of development, with the high molecular weight (HMW) gliadins appearing at about 20 days after anthesis (Pavlov et al 1975;Zairov et al 1982).…”

Expression and Development of Wheat Proteins during Maturation of Wheat Kernel and the Rheological Properties of Dough Prepared from the Flour of Mature and Immature Wheat

“…Grimwade et al (1996) reported that mRNAs for the various groups of gluten proteins were detected from 11 days after anthesis, and the proteins were detected from about 14 days after anthesis. When using acidic-polyacrylamide gel electrophoresis (A-PAGE), the gliadin bands became visible at about 6 days (Greene et al, 1985), 10 days (Bartels and Thompson, 1986;Johansson et al, 1994;Ng et al, 1990), 8 -12 days (Skerritt et al, 1988), and 12 -15 days (Mecham et al, 1981) after anthesis. The glutenin banding patterns on sodium dodecylsulfate-PAGE (SDS-PAGE) were detectable at 8 days (Skerritt et al, 1988), 10 days (Bartels and Thompson, 1986;Shewry et al, 2009), 13 days (Ng et al, 1990), and 14 days (Johansson et al, 1994) after anthesis.…”

“…As described above, several authors have studied compositional changes in gluten proteins during kernel development (Abonyi et al, 2007;Bartels and Thompson, 1986;Greene et al, 1985;Grimwade et al, 1996;Iametti et al, 2006;Johansson et al, 1994;Mecham et al, 1981;Ng et al, 1990;Skerritt et al, 1988). However, relatively few studies have examined individual gluten proteins at the subunit level.…”

Identification and DNA sequence analysis of a ?-type gliadin cDNA plasmid from winter wheat

“…During seed development, expression of these proteins is developmentally regulated. Gliadin synthesis begins about 10-15 days after flowering and continues until the onset of seed maturation (13,21). These proteins are preferentially synthesized on membrane polysomes (8,12) and are packaged into membrane limited protein bodies (11).…”