Physiological and Proteomic Analyses of Saccharum spp. Grown under Salt Stress

Abstract

Sugarcane (Saccharum spp.) is the world most productive sugar producing crop, making an understanding of its stress physiology key to increasing both sugar and ethanol production. To understand the behavior and salt tolerance mechanisms of sugarcane, two cultivars commonly used in Brazilian agriculture, RB867515 and RB855536, were submitted to salt stress for 48 days. Physiological parameters including net photosynthesis, water potential, dry root and shoot mass and malondialdehyde (MDA) content of leaves were determined. Control plants of the two cultivars showed similar values for most traits apart from higher root dry mass in RB867515. Both cultivars behaved similarly during salt stress, except for MDA levels for which there was a delay in the response for cultivar RB867515. Analysis of leaf macro- and micronutrients concentrations was performed and the concentration of Mn2+ increased on day 48 for both cultivars. In parallel, to observe the effects of salt stress on protein levels in leaves of the RB867515 cultivar, two-dimensional gel electrophoresis followed by MS analysis was performed. Four proteins were differentially expressed between control and salt-treated plants. Fructose 1,6-bisphosphate aldolase was down-regulated, a germin-like protein and glyceraldehyde 3-phosphate dehydrogenase showed increased expression levels under salt stress, and heat-shock protein 70 was expressed only in salt-treated plants. These proteins are involved in energy metabolism and defense-related responses and we suggest that they may be involved in protection mechanisms against salt stress in sugarcane.

Label‐Free Quantitative Proteomics of Enriched Nuclei from Sugarcane (Saccharum ssp) Stems in Response to Drought Stress

“…Similarly, two accessions of alfin‐like proteins (AT3G42790, AT5G20510) showed increased abundance. In chickpea roots, the alfin‐like gene homologous AT1G14510 was one of the most up‐regulated genes in response to drought …”

“…Such increased abundance of transcription‐ and translation‐related proteins might be associated with a mechanism for enhancing the production of proteins related to defense against drought stress. Other studies have reported complex results of the protein metabolism in response to different stresses …”

Proteomic Analysis of Copper-Binding Proteins in Excess Copper-Stressed Roots of Two Rice (Oryza sativa L.) Varieties with Different Cu Tolerances

“…Proteomic analyses of proteins responsive to ion toxicity in several plant species also showed that expression of CuZn-SOD was stimulated by Cd and Al [ 23 , 24 ]. Increased expression of certain GLPs or genes was also observed in various plants under drought, salt, Al and heavy metal stresses (Cd 2+ , Cu 2+ and Co 2+ ), and pathogen invasion [ 19 , 25 , 26 ]. However, to our knowledge, no proteomics-based study on metal-induced alterations of CuZn-SOD and GLPs as Cu-IMAC-binding proteins in plants has been published.…”

Sugarcane proteomics: An update on current status, challenges, and future prospects

“…Introduction of 2DE by O'Farrell had rejuvenated and rekindled interest on sugarcane proteomics as evidenced by an influx of research papers during the late 1980s and after by employing 2DE to study sugarcane‐suspension cells , meristem , leaves , stalk , root . Moisyadi and Harrington employed tube gels and 2DE to analyze the effect of heat shock treatments on cultured sugarcane cells.…”

“…proteomics-based studies in sugarcane from 1975 to 1989, probably due to intervention of genomic tools like PCR that has revolutionized genomics and made it seem more attractive and promising than proteomics at that point of time. Introduction of 2DE by O'Farrell [26] had rejuvenated and rekindled interest on sugarcane proteomics as evidenced by an influx of research papers during the late 1980s and after by employing 2DE to study sugarcane-suspension cells [27,28], meristem [29], leaves [30][31][32][33][34][35][36][37][38][39][40], stalk [41], root [42]. Moisyadi and Harrington [27] employed tube gels and 2DE to analyze the effect of heat shock treatments on cultured sugarcane cells.…”