title: Identification of Low Molecular Weight Glutenin Alleles by Matrix-Assisted Laser Desorption/Ionization Time-Of-Flight Mass Spectrometry (MALDI-TOF-MS) in Common Wheat (Triticum aestivum L.).
abstract: Low molecular weight glutenin subunits (LMW-GS) play an important role in determining dough properties and breadmaking quality. However, resolution of the currently used methodologies for analyzing LMW-GS is rather low which prevents an efficient use of genetic variations associated with these alleles in wheat breeding. The aim of the current study is to evaluate and develop a rapid, simple, and accurate method to differentiate LMW-GS alleles using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. A set of standard single LMW-GS allele lines as well as a suite of well documented wheat cultivars were collected from France, CIMMYT, and Canada. Method development and optimization were focused on protein extraction procedures and MALDI-TOF instrument settings to generate reproducible diagnostic spectrum peak profiles for each of the known wheat LMW-GS allele. Results revealed a total of 48 unique allele combinations among the studied genotypes. Characteristic MALDI-TOF peak patterns were obtained for 17 common LMW-GS alleles, including 5 (b, a or c, d, e, f), 7 (a, b, c, d or i, f, g, h) and 5 (a, b, c, d, f) patterns or alleles for the Glu-A3, Glu-B3, and Glu-D3 loci, respectively. In addition, some reproducible MALDI-TOF peak patterns were also obtained that did not match with any known alleles. The results demonstrated a high resolution and throughput nature of MALDI-TOF technology in analyzing LMW-GS alleles, which is suitable for application in wheat breeding programs in processing a large number of wheat lines with high accuracy in limited time. It also suggested that the variation of LMW-GS alleles is more abundant than what has been defined by the current nomenclature system that is mainly based on SDS-PAGE system. The MALDI-TOF technology is useful to differentiate these variations. An international joint effort may be needed to assign allele symbols to these newly identified alleles and determine their effects on end-product quality attributes.
authors.affiliation: State Agriculture Biotechnology Centre, School of Veterinary & Life Sciences, Murdoch University, Australia Export Grains Innovation Centre (AEGIC), Perth, WA, 6150, Australia; Key Laboratory of Genetics and Biotechnology, College of Life Science, Capital Normal University, Beijing, 100037, China.
authors.forename: Aili
authors.initials: A
authors.lastname: Wang
authors.affiliation: State Agriculture Biotechnology Centre, School of Veterinary & Life Sciences, Murdoch University, Australia Export Grains Innovation Centre (AEGIC), Perth, WA, 6150, Australia; National Wheat Improvement Centre, Institute of Crop Sciences, Chinese Academy of Agricultural Sciences (CAAS), No. 12 Zhongguancun South Street, Beijing, 100081, China.
authors.forename: Li
authors.initials: L
authors.lastname: Liu
authors.affiliation: State Agriculture Biotechnology Centre, School of Veterinary & Life Sciences, Murdoch University, Australia Export Grains Innovation Centre (AEGIC), Perth, WA, 6150, Australia; College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, 430070, Hubei, China.
authors.forename: Yanchun
authors.initials: Y
authors.lastname: Peng
authors.affiliation: State Agriculture Biotechnology Centre, School of Veterinary & Life Sciences, Murdoch University, Australia Export Grains Innovation Centre (AEGIC), Perth, WA, 6150, Australia.
authors.forename: Shahidul
authors.initials: S
authors.lastname: Islam
authors.affiliation: South Australian Research & Development Institute, Waite Campus, 2b Hartley Grove, Urrbrae, SA, 5064, Australia.
authors.forename: Marie
authors.initials: M
authors.lastname: Applebee
authors.affiliation: State Agriculture Biotechnology Centre, School of Veterinary & Life Sciences, Murdoch University, Australia Export Grains Innovation Centre (AEGIC), Perth, WA, 6150, Australia.
authors.forename: Rudi
authors.initials: R
authors.lastname: Appels
authors.affiliation: Key Laboratory of Genetics and Biotechnology, College of Life Science, Capital Normal University, Beijing, 100037, China.
authors.forename: Yueming
authors.initials: Y
authors.lastname: Yan
authors.affiliation: State Agriculture Biotechnology Centre, School of Veterinary & Life Sciences, Murdoch University, Australia Export Grains Innovation Centre (AEGIC), Perth, WA, 6150, Australia.
authors.forename: Wujun
authors.initials: W
authors.lastname: Ma
mesh_terms: D000483:Alleles; D005983:Glutens / Q000235:genetics* / Q000378:metabolism; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D014908:Triticum / Q000235:genetics* / Q000378:metabolism
chemical_list: D005983:Glutens; C037302:glutenin