Allelic variation of LMW-GS composition in Chinese wheat landraces of the Yangtze-River region detected by MALDI-TOF-MS

Abstract

Low molecular weight glutenin subunits are important components of wheat storage proteins, which play an important role in determining end-use quality of common wheat. A newly established matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) procedure was used to analyze 478 landraces of bread wheat collected from the Yangtze-River region in China. Results indicated that 17 alleles at three loci: Glu-A3, Glu-B3 and Glu-D3 were identified, resulting in 87 different allele combinations. Of the 17 alleles detected at all the Glu-3 loci, five belonged to Glu-A3, seven to Glu-B3 and five to Glu-D3 locus. MALDI-TOF-MS indicated Glu-A3a/c was present in 72.8%, Glu-A3b in 8.4%, Glu-A3d in 8.4%, Glu-A3f in 5.2% and Glu-A3e in 3.6% lines. Seven types of alleles were identified at the Glu-B3 locus: Glu-B3d/i (25.5%), Glu-B3b (21.3%), Glu-B3c (16.9%), Glu-B3h (13.8%), Glu-B3f (8.4%), Glu-B3a (8.2%), and Glu-B3g (5.2%). Five types of Glu-D3 alleles were detected: Glu-D3a (58.4%), Glu-D3c (22.6%), Glu-D3d (15.5%), Glu-D3b (3.3%) and Glu-D3f (0.2%). Four new alleles that showed abnormal MALDI-TOF spectrum patterns were identified at the Glu-A3 and Glu-B3 loci. A detailed study is needed to further characterize these alleles and their potential usage for wheat improvement.

Allelic variation of low molecular weight glutenin subunits composition and the revealed genetic diversity in durum wheat (<i>Triticum turgidum</i> L. ssp. <i>durum</i> (Desf))

“…Several novel alleles were identified in landraces collected from Yangtze-River region of China in our research and in Peng et al (2016) and Wang et al (2015) at Glu-A3 and Glu-B3 loci. It should be mentioned that Peng et al (2016) and Wang et al (2015) found two novel subunits associated with the spectrum peaks 41,758 Da at Glu-A3 and 40,499 Da at Glu-B3 . In our research, we also detected the spectrum peaks with similar masses of approximately 41,758 Da and 40,499 Da.…”

“…Most LMW-GS compositions of durum wheat materials can be detected rapidly and easily according to the characteristic peaks of standard samples in Wang et al (2015). Several novel alleles were identified in landraces collected from Yangtze-River region of China in our research and in Peng et al (2016) and Wang et al (2015) at Glu-A3 and Glu-B3 loci. It should be mentioned that Peng et al (2016) and Wang et al (2015) found two novel subunits associated with the spectrum peaks 41,758 Da at Glu-A3 and 40,499 Da at Glu-B3 .…”

“…One-dimensional SDS-PAGE, 2-DE (two-dimensional gel electrophoresis (IEF × SDS-PAGE)) and HPLC (High performance liquid chromatography) methods have been generally used to identify and select specific HMW-GS and LMW-GS with superior quality in many breeding programs (Dworschak et al 1998, Yahata et al 2005). Matrix-assisted laser desorption/ionization time-of flight (MALDI-TOF-MS) is an effective and very important approach in rapidly and easily identifying glutenin subunits for its high accuracy and sensitivity in analyzing samples, which has been particularly useful in wheat quality breeding programs (Dworschak et al 1998, Elfatih et al 2013, Liu et al 2009, 2010, Peng et al 2016, Zheng et al 2011). MALDI-TOF-MS has widely been used to identify the HMW-GS compositions of common landraces of bread wheat collected from the Yangtze-River region of China (Zheng et al 2011), to detect the compositions of HMW-GS in durum wheat from different countries (Elfatih et al 2013), to establish an analytical standard for identifying LMW-GS using a set of 19 near-isogenic lines (NIL) of cultivar Aroona (Wang et al 2015).…”

Characterization of Pakistani wheat germplasm for high and low molecular weight glutenin subunits using SDS-PAGE

“…Contrary to our findings, Park et al (2011) reported maximum frequency of Glu-A3d in genotypes of Korean wheat while the same frequency was also detected in Japanese and French wheat (Branlard et al 2001;Tanaka et al 2005). However, our results are analogous to the previous findings (Branlard et al 2003;Bellil et al 2010;Bradová and Štočková 2010;Liu et al 2010;Ram et al 2011;Peng et al 2016) where tested varieties possessed leading frequency of Glu-A3c allele i.e. 49.3%, 47.0%, 44.5%, 72.5%, 40.3%, 64.6% respectively.…”

“…Wheat glutenin proteins, especially high molecular weight and low molecular weight glutenin subunits accumulated in starchy endosperm have a vital part in defining the bread-making as well as dough characteristics and hence the nutritional quality of flour (Anjum et al 2007;Peng et al 2016). According to the research, HMW-glutenin subunits composition variation may be the reason behind rate of inter varietal differences in bread forming capability while LMW-GS have not attained that much attention as HMW-GS because of intricate banding pattern and mobility overlapping with glaidin (Park et al 2011), so this makes it necessary to evaluate the variation in alleles of high molecular weight as well as low molecular weight glutenin subunits conformation liable for bread manufacturing quality amongst wheat varieties of Pakistan (Tabasum et al 2011).…”