Mustafa Ghazala, Komatsu Setsuko
Graduate School of Life and Environmental Science, University of Tsukuba Tsukuba, Japan ; National Institute of Crop Science, National Agriculture and Food Research Organization Tsukuba, Japan.
Front Plant Sci. 2014 Nov 18;5:627. doi: 10.3389/fpls.2014.00627. eCollection 2014.
Flooding stress has a negative impact on soybean cultivation because it severely impairs growth and development. To understand the flooding responsive mechanism in early stage soybeans, a glycoproteomic technique was used. Two-day-old soybeans were treated with flooding for 2 days and roots were collected. Globally, the accumulation level of glycoproteins, as revealed by cross-reaction with concanavalin A decreased by 2 days of flooding stress. Glycoproteins were enriched from total protein extracts using concanavalin A lectin resin and analyzed using a gel-free proteomic technique. One-hundred eleven and 69 glycoproteins were identified without and with 2 days of flooding stress, respectively. Functional categorization of these identified glycoproteins indicated that the accumulation level of proteins related to protein degradation, cell wall, and glycolysis increased, while stress-related proteins decreased under flooding stress. Also the accumulation level of glycoproteins localized in the secretory pathway decreased under flooding stress. Out of 23 common glycoproteins between control and flooding conditions, peroxidases and glycosyl hydrolases were decreased by 2 days of flooding stress. mRNA expression levels of proteins in the endoplasmic reticulum and N-glycosylation related proteins were downregulated by flooding stress. These results suggest that flooding might negatively affect the process of N-glycosylation of proteins related to stress and protein degradation; however glycoproteins involved in glycolysis are activated.
淹水胁迫对大豆种植有负面影响，因为它会严重损害大豆的生长发育。为了解早期大豆的淹水响应机制，采用了糖蛋白质组学技术。对两天大的大豆进行淹水处理2天，然后收集根系。总体而言，通过与伴刀豆球蛋白A交叉反应显示，淹水胁迫2天后糖蛋白的积累水平下降。使用伴刀豆球蛋白A凝集素树脂从总蛋白提取物中富集糖蛋白，并采用无凝胶蛋白质组学技术进行分析。分别在未受淹水胁迫和受淹水胁迫2天的情况下，鉴定出111种和69种糖蛋白。对这些鉴定出的糖蛋白进行功能分类表明，在淹水胁迫下，与蛋白质降解、细胞壁和糖酵解相关的蛋白质积累水平增加，而与胁迫相关的蛋白质减少。此外，位于分泌途径中的糖蛋白积累水平在淹水胁迫下也降低。在对照和淹水条件下的23种常见糖蛋白中，淹水胁迫2天后过氧化物酶和糖基水解酶减少。内质网中的蛋白质和N-糖基化相关蛋白质的mRNA表达水平因淹水胁迫而下调。这些结果表明，淹水可能会对与胁迫和蛋白质降解相关的蛋白质的N-糖基化过程产生负面影响；然而，参与糖酵解的糖蛋白被激活。
