Comparative Proteomic Analysis of Two Barley Cultivars (Hordeum vulgare L.) with Contrasting Grain Protein Content

Abstract

Grain protein contents (GPCs) of barley seeds are significantly different between feed and malting barley cultivars. However, there is still no insight into the proteomic analysis of seed proteins between feed and malting barley cultivars. Also, the genetic control of barley GPC is still unclear. GPCs were measured between mature grains of Yangsimai 3 and Naso Nijo. A proteome profiling of differentially expressed protein was established by using a combination of 2-DE and tandem mass spectrometry. In total, 502 reproducible protein spots in barley seed proteome were detected with a pH range of 4–7 and 6–11, among these 41 protein spots (8.17%) were detected differentially expressed between Yangsimai 3 and Naso Nijo. Thirty-four protein spots corresponding to 23 different proteins were identified, which were grouped into eight categories, including stress, protein degradation and post-translational modification, development, cell, signaling, glycolysis, starch metabolism, and other functions. Among the identified proteins, enolase (spot 274) and small subunit of ADP-glucose pyrophosphorylase (spot 271) are exclusively expressed in barley Yangsimai 3, which may be involved in regulating seed protein expression. In addition, malting quality is characterized by an accumulation of serpin protein, Alpha-amylase/trypsin inhibitor CMb and Alpha-amylase inhibitor BDAI-1. Most noticeably, globulin, an important storage protein in barley seed, undergoes post-translational processing in both cultivars, and also displays different expression patterns.

Protein Profiles of Cereals and Pseudocereals Determined by Two-Dimensional Gel Electrophoresis

“…A group of intense spots of low molecular mass (6-21000 Da) and pI 4.5 of 5.5 (marked as a), were observed which corresponded to alpha-amylase/trypsin inhibitor proteins previously identified in developing barley seeds by Akagawa et al (Akagawa et al, 2007), Finnie et al (Finnie et al, 2002), Østergaard et al (Østergaard et al, 2004), Perrocheau et al (Perrocheau et al, 2005). A second group of alpha-amylase/trypsin inhibitor proteins have been previously identified with a low molecular weight range from 12-16000 Da and pI 5-7 (Bak-Jensen et al, 2004;Guo et al, 2016;) and could be the group of proteins highlighted between 12-21000 Da (marked as d, e). Perrocheau et al (Perrocheau et al, 2005) identified the hordeins and 12 S seed storage proteins, which were observed on both the pH 3-11 gel (marked as b) and 6-11 gels (marked as c) in the range of 35-45000 Da, in the pI 6-8 range.…”

“…Then, focussing on the gluten fraction, as it is the major trigger for celiac disease, we separated proteins with a basic pI over a narrow pH range of pH 6-11. Putative identifications of proteins were obtained using current literature for each type of crop (Rocher et al, 1992;Varjonen et al, 1994;Rocher et al, 1996;James et al, 1997;Aalberse, 2000;Skylas et al, 2000;Finnie et al, 2002;Gellrich et al, 2003;Bak-Jensen et al, 2004;Østergaard et al, 2004;Perrocheau et al, 2005;Anderson and Wieser, 2006;Akagawa et al, 2007;Dupont et al, 2011;Londono et al, 2013;Vensel et al, 2014;Guo et al, 2016;Klubicová et al, 2016;Malalgoda and Simsek, 2017;Nałęcz et al, 2017;Zhou et al, 2018).…”

“…We could not assign any identifications to the group of intense unidentifiable protein spots of low molecular mass (10-20000 Da) and pI 6 of 8 (marked as f). Guo et al (Guo et al, 2016) identified 502 reproducible protein spots in barley seed proteome were detected with a pH range of 4-7 and 6-11. Thirty-four protein spots corresponding to 23 different proteins were identified, which were grouped into eight categories, including stress, protein degradation and post-translational modification, development, cell, signaling, glycolysis, starch metabolism, and other functions.…”

Comparative analyses of albumin/globulin grain proteome fraction in differentially salt‐tolerant Tunisian barley landraces reveals genotype‐specific and defined abundant proteins

“…Among cereals, barley ( Hordeum vulgare L.) is one of the oldest and most important cultivated crops, which ranks fourth in terms of production in the world (Guo et al . ). Furthermore, it is also well studied in terms of genetics, genomics and breeding and thus qualifies as a model plant for Triticeae research.…”

Physiological Processes Contributing to the Difference in Grain Amino Acid Content between Two Hybrid Rice (Oryza sativa L.) Cultivars

“…Proteomic analysis is a powerful approach that can provide qualitative and quantitative information of protein expression, which is invaluable in understanding the mechanisms involved in physiological processes [11]. This approach has been successfully used to provide new insights into the mechanisms underlying grain quality traits in cereals [12][13][14]. However, no such report is available for the grain amino acid content in rice.…”