Proteomic analysis of rice leaves during drought stress and recovery

Abstract

Three-week old plants of rice (Oryza sativa L. cv CT9993 and cv IR62266) developed gradual water stress over 23 days of transpiration without watering, during which period the mid-day leaf water potential declined to approximately -2.4 MPa, compared with approximately -1.0 MPa in well-watered controls. More than 1000 protein spots that were detected in leaf extracts by proteomic analysis showed reproducible abundance within replications. Of these proteins, 42 spots showed a significant change in abundance under stress, with 27 of them exhibiting a different response pattern in the two cultivars. However, only one protein (chloroplast Cu-Zn superoxide dismutase) changed significantly in opposite directions in the two cultivars in response to drought. The most common difference was for proteins to be up-regulated by drought in CT9993 and unaffected in IR62266; or down-regulated by drought in IR62266 and unaffected in CT9993. By 10 days after rewatering, all proteins had returned completely or largely to the abundance of the well-watered control. Mass spectrometry helped to identify 16 of the drought-responsive proteins, including an actin depolymerizing factor, which was one of three proteins detectable under stress in both cultivars but undetectable in well-watered plants or in plants 10 days after rewatering. The most abundant protein up-regulated by drought in CT9993 and IR62266 was identified only after cloning of the corresponding cDNA. It was found to be an S-like RNase homologue but it lacked the two active site histidines required for RNase activity. Four novel drought-responsive mechanisms were revealed by this work: up-regulation of S-like RNase homologue, actin depolymerizing factor and rubisco activase, and down-regulation of isoflavone reductase-like protein.

Proteomics Analysis of Drought Stress-Responsive Proteins in Hippophae rhamnoides L.

“…Vincent et al (2005) have applied 2-DE profiling to elucidate the impact of water deficiency on the lignification of maize leaves. The protein profiling of rice leaves subjected to drought revealed four novel droughtresponsive mechanisms (Salekdeh et al 2002a, b): upregulation of a S-like RNase homologue, an actin depolymerizing factor and a rubisco activase, and down-regulation of an isoflavone reductase-like protein (Salekdeh et al 2002a). Additionally, the response of the proteome of field-grown sugar beet leaves to drought stress has been studied (Hajheidari et al 2005).…”

Research on the Rice Proteome: The Contribution of Proteomics Technology in the Creation of Abiotic Stress-Tolerant Plants

“…Salekdeh et al [49] compared protein expression in 3-week-old plants of the drought-tolerant rice cultivars IR62266 and CT9993. Out of 1,000 proteins in leaves, the expression of SOD changed significantly under drought, but in opposing directions, in the two cultivars.…”

“…The proteins that most increased in abundance in response to drought were S-like RNase homolog, actin-depolymerizing factor, and ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBisCO) activase, whereas the protein that showed the greater decrease in abundance was isoflavone reductase-like protein. The reports of Ali and Komatsu [4] and Salekdeh et al [49], taken together, suggest that actin depolymerizing factor is one of the target proteins that is induced by drought stress. The up-regulation of actin depolymerizing factor under drought stress and salt stress [57] indicates that this protein might be involved in dynamic reorganization of cytoskeleton during osmotic stress.…”

“…Although eight of these are known salt-stress response proteins, the majority have not been reported in the literature. In proteomic studies, the level of different SOD isoforms were found up-regulated under drought [4,49], salt [1,44], and ozone [2,15]. SOD activity, determined by multigene family, is changing under different environmental conditions.…”

Physiological and comparative proteomic analyses of Thai jasmine rice and two check cultivars in response to drought stress

“…However, studies of rice proteomes under drought stress have been limited to only a few cultivars with most studies being conducted with japonica rice (Oryza sativa L. ssp. japonica) using conventional 2D-PAGE-based proteomic analysis (Salekdeh et al 2002;Ali & Komatsu 2006;Zang and Komatsu 2007). Moreover, there is no convincing evidence on the suitability of osmotic agents for generating osmotic stress in rice seedlings to simulate drought conditions.…”