Proteomics Analysis of Alfalfa Response to Heat Stress

Abstract

The proteome responses to heat stress have not been well understood. In this study, alfalfa (Medicago sativa L. cv. Huaiyin) seedlings were exposed to 25°C (control) and 40°C (heat stress) in growth chambers, and leaves were collected at 24, 48 and 72 h after treatment, respectively. The morphological, physiological and proteomic processes were negatively affected under heat stress. Proteins were extracted and separated by two-dimensional polyacrylamide gel electrophoresis (2-DE), and differentially expressed protein spots were identified by mass spectrometry (MS). Totally, 81 differentially expressed proteins were identified successfully by MALDI-TOF/TOF. These proteins were categorized into nine classes: including metabolism, energy, protein synthesis, protein destination/storage, transporters, intracellular traffic, cell structure, signal transduction and disease/defence. Five proteins were further analyzed for mRNA levels. The results of the proteomics analyses provide a better understanding of the molecular basis of heat-stress responses in alfalfa.

Physiological and proteome studies of responses to heat stress during grain filling in contrasting wheat cultivars

“…Aspartate aminotransferase, which transfers an ␣-amino group between aspartate and glutamate, is an important enzyme in amino acid metabolism [86]. Aspartate aminotransferase increased in abundance under heat stress in alfalfa [87]. In the current study, aspartate aminotransferase increased in abundance in cv.…”

Screening for salt-responsive proteins in two contrasting alfalfa cultivars using a comparative proteome approach

“…In this study, increased level of proline and soluble sugars level in NM-801 possibly contributed to osmoregulatory response to salt and functioned as protective agents against ROS. The level of compatible solutes (proline, sugar) was also found to be increased by drought and heat stresses in alfalfa (Kang et al, 2011;Li et al, 2013). The high amounts of proline and sugar accumulated possibly play a vital role as osmoprotection and in free radical homeostasis in NM-801, contributing to its greater salt tolerance compared to VN.…”

Selection and Breeding of Suitable Crop Genotypes for Drought and Heat Periods in a Changing Climate: Which Morphological and Physiological Properties Should Be Considered?

“…Different types of tissues are studied: roots [141,154,159], root nodules [161], leaves [138,160], roots and leaves compared at seedling stage [157], roots, flag leaves and spikelets at reproductive stage [151]. As the high temperature is particularly detrimental during the reproductive stage, besides the studies on leaf proteome under heat stress in rice [113,162], wheat [163] radish [142], alfalfa [164] and stromal proteins in agave [165], special attention is paid to the reproductive phase [166], source-sink interactions at grain filling [167], grain development and composition [155,160] in cereals, and protein composition of soybean seeds [168] formed under unfavorable temperature conditions. Relatively few proteomic studies deal with combined drought and heat stress [169][170][171].…”