Two Novel Y-Type High Molecular Weight Glutenin Genes in Chinese Wheat Landraces of the Yangtze-River Region

Abstract

High molecular weight glutenin subunits (HMW-GSs) are key determinants for the end-use quality of wheat. Chinese wheat landraces are an important resource for exploring novel HMW-GS genes to improve the wheat baking quality. Two novel Glu-1Dy HMW-GSs (designated as 1Dy12.6 and 1Dy12.7) were identified and cloned from two Chinese wheat landraces Huazhong830 and Luosimai. The 1Dy12.6 and 1Dy12.7 subunits were deposited as the NCBInr Acc. No KR262518, and KR262519, respectively. The full open reading frames (ORFs) of 1Dy12.6 and 1Dy12.7 were 2022 bp and 1977 bp, encoding for proteins of 673 and 658 amino acid residues, respectively. Each contains four typical primary regions of HMW-GSs (a signal peptide, N- and C-terminal regions, and a central repetitive region). Their deduced molecular masses (70,165 Da and 68,400 Da) were strikingly consistent with those identified by MALDI-TOF-MS (69,985Da and 68,407 Da). The 1Dy12.6 is the largest 1Dy glutenin subunits cloned in common wheat up to date, containing longer repetitive central domains than other 1Dy encoded proteins. In comparison with the most similar active 1Dy alleles previously reported, the newly discovered alleles contained a total of 20 SNPs and 3 indels. The secondary structure prediction indicated that 1Dy12.6 and 1Dy12.7 have similar proportion of α-helix, β-turn, and β-bend to those of 1Dy10 (X12929). The phylogenetic analysis illustrated that the x- and y-type subunits of glutenins were well separated, but both 1Dy12.6 and 1Dy12.7 were clustered with the other Glu-1Dy alleles. Our results revealed that the 1Dy12.6 and 1Dy12.7 subunit have potential to strengthen gluten polymer interactions, and are valuable genetic resources for wheat quality improvement.

Expressed Ay HMW glutenin subunit in Australian wheat cultivars indicates a positive effect on wheat quality

“…The gene encoding i 1Ay subunit was usually silenced in wheat (8) and expressed combination of 1Ax+1Ay subunits had only been identified in some diploid and tetraploid wheat germplasm (9). It is known that the y-type subunits contain more cysteine residues M A N U S C R I P T A C C E P T E D ACCEPTED MANUSCRIPT than x-type, making it more valuable to improve flour quality because of its higher potential to form more inter and intramolecular disulfide bonds (10). It has been proved that 1Ay has positive effect in bread making quality, Rogers el al.…”

High-Molecular-Weight Glutenin Subunits: Genetics, Structures, and Relation to End Use Qualities

“…Besides, the solubility of glutenin subunits from gluten would be similar to gliadins in aqueous alcohols if the disulfide bonds are reduced [ 8 ]. Based on their electrophoresis mobility on a sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), reduced glutenin from dough can be further categorized into High-molecular-weight glutenin subunits (HMW-GSs, MW of 67,000–90,000 Da) and low-molecular-weight glutenin subunits (LMW-GSs, MW of 30,000–45,000 Da) [ 11 , 12 , 13 , 14 ]. Though HMW-GSs are minor components in terms of mass (approximately 10% of gluten protein), they are highly related to end use quality [ 8 ].…”

Rapid and Easy High-Molecular-Weight Glutenin Subunit Identification System by Lab-on-a-Chip in Wheat (Triticum aestivum L.)

“…Reverse-phase high-performance liquid chromatography (RP-HPLC) was developed and used to discriminate the allelic variation of HMW-GS [5,27]. In addition, several other methods, such as high-performance capillary electrophoresis (HPCE), matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS), and Lab-on-a-chip capillary electrophoresis (Lab-on-a-chip) were applied to identify the composition of HMW-GS [28][29][30][31]. Of these methods, MALDI-TOF-MS is said to be appropriate for detecting new allelic variations of HMW-GS [29].…”

“…In addition, several other methods, such as high-performance capillary electrophoresis (HPCE), matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS), and Lab-on-a-chip capillary electrophoresis (Lab-on-a-chip) were applied to identify the composition of HMW-GS [28][29][30][31]. Of these methods, MALDI-TOF-MS is said to be appropriate for detecting new allelic variations of HMW-GS [29]. However, SDS-PAGE, RP-HPLC, and MALDI-TOF-MS analysis are time-consuming and require a certain number of processes [32].…”