Proteomics Revealed Distinct Responses to Salinity between the Halophytes Suaeda maritima (L.) Dumort and Salicornia brachiata (Roxb)

Abstract

Plant resistance to salinity stress is one of the main challenges of agriculture. The comprehension of the molecular and cellular mechanisms involved in plant tolerance to salinity can help to contrast crop losses due to high salt conditions in soil. In this study, Salicornia brachiata and Suaeda maritima, two plants with capacity to adapt to high salinity levels, were investigated at proteome level to highlight the key processes involved in their tolerance to NaCl. With this purpose, plants were treated with 200 mM NaCl as optimal concentration and 500 mM NaCl as a moderate stressing concentration for 14 days. Indeed, 200 mM NaCl did not result in an evident stress condition for both species, although photosynthesis was affected (with a general up accumulation of photosynthesis-related proteins in S. brachiata under salinity). Our findings indicate a coordinated response to salinity in both the halophytes considered, under NaCl conditions. In addition to photosynthesis, heat shock proteins and peroxidase, expansins, signaling processes, and modulation of transcription/translation were affected by salinity. Interestingly, our results suggested distinct mechanisms of tolerance to salinity between the two species considered, with S. brachiata likely having a more efficient mechanism of response to NaCl.

Image and fractal analysis as a tool for evaluating salinity growth response between two Salicornia europaea populations

“…When plants are exposed to high salinity, they induce a reduced stomatal conductance as a strategic mechanism to decrease the net uptake of salt ions and to conserve water in the plant, causing a mesophyll thickening of the shoot [10]. The lower stomatal conductance mechanism leads to the generation of reactive oxygen species (ROS) while at the same time CO 2 fixation is reduced, inducing a photosynthetic decrease, which is reflected in changes of the plant pigments due to the reduction in chlorophyll content.…”

Research Advances on Molecular Mechanism of Salt Tolerance in Suaeda

“…The salinity-responsive proteins belong to various functions including ROS scavenging, ionic and osmotic regulation, signal transduction, and photosynthesis [ 111 ]. In S. maritima , photosynthesis, heat shock proteins, peroxidase, expansins, signaling processes, and modulation of transcription/translation were modulated by salinity [ 112 ]. In S. salsa , three upregulated and six downregulated proteins were identified, involved in photosynthesis, energy metabolism, stress, and defense [ 109 ].…”

“…The enhancement of nontoxic metabolites may stimulate the expression of salt-tolerance proteins in S. maritima [ 52 ]. Acetolactate synthase 1 and histone H4 were up- and down-accumulated in S. maritima at the lower (200 mM) and higher (500 mM) NaCl dosages, respectively [ 112 ]. In S. maritima , cytochrome b6f complex, cytosolic, expansin-B1, chloroplastic GAPDH, and the chloroplastic ATP synthase subunit α were downregulated with salt treatment, resulting in a reduction of photosynthetic activity [ 112 ].…”

“…Acetolactate synthase 1 and histone H4 were up- and down-accumulated in S. maritima at the lower (200 mM) and higher (500 mM) NaCl dosages, respectively [ 112 ]. In S. maritima , cytochrome b6f complex, cytosolic, expansin-B1, chloroplastic GAPDH, and the chloroplastic ATP synthase subunit α were downregulated with salt treatment, resulting in a reduction of photosynthetic activity [ 112 ]. Thus, proteomics is helpful to understand the characterization of interactions and the response to salt stress in Suaeda plants.…”

Métodos computacionais para detecção de plasticidade vegetal em >i<Tradescantia minima>/i< causada por agentes tóxicos

“…As abordagens ômicas, como genômica, transcriptômica, proteômica e metabolômica, são respostas essenciais da planta para se adaptar à salinidade e melhorar a produtividade. 123 A fotossíntese é um dos processos físico-químicos mais importantes, mas é muito sensível à salinidade. A salinidade leva a uma redução da fotossíntese ao tornar os estômatos sensíveis.…”