Portal de Periódicos da CAPES

Parallel analysis of proteins in brown seaweed Sargassum fusiforme responding to hyposalinity stress

2016; Elsevier BV; Volume: 465; Linguagem: Inglês

10.1016/j.aquaculture.2016.08.032

1873-5622

Weiguo Qian, Nan Li, Lidong Lin, Tao Xu, Xu Zhang, Lihua Wang, Huixi Zou, Mingjiang Wu, Xiufeng Yan,

Marine Biology and Ecology Research

The intertidal seaweed Sargassum fusiforme shows remarkable tolerances to freshwater immersion, which made experienced cultivators quite convenient to control epiphytic algae that would limit the massive aquaculture production. Here, we performed biochemical and physiological analyses and comparative proteomics to investigate the molecular mechanisms of the hyposalinity-stress-tolerance in S. fusiforme. Our results showed that in the initial period of freshwater immersion, mineral fraction and inorganic anion may be lost much faster than other soluble contents. H2O2 accumulation occurred immediately and the antioxidant system was efficiently activated during freshwater immersion. Comparative proteomic analysis revealed 51 differentially expressed protein spots in S. fusiforme, most of which were enzymes involved in photosynthesis, carbohydrate metabolism and energy metabolism. The one-hour's-freshwater-immersion negatively affected the metabolic activity of S. fusiforme, as synthesis of most key metabolic enzymes were inhibited in varying degrees, with only a few exceptions, e.g., phosphomannomutase, which is related to precursor synthesis of cell wall polysaccharides. In order to eliminate other wild harmful algae, freshwater or lower salinity of seawater is usually employed to the brown alga Sargassum fusiforme for a short period, indicating its tolerance to hyposalinity stress. Osmotic stress is one of the major abiotic stresses for most algae. As most studies were concerning about the hypersalinity stress, physiological mechanisms of tolerance to hyposalinity stress of algae are not fully understood. This study focuses on responses of the brown alga S. fusiforme to short-term (or acute) hyposalinity stress, using comparative physiology approach combining methods of systems biology including proteomics. Then analyzes the typical physiological characteristics related to osmotic stress and overall physiological metabolic networks to investigate the possible tolerance mechanism of S. fusiforme to hyposalinity stress at physiological level. As an important foundation work, analyzing the effect of hyposalinity stress on the survival of S. fusiforme and its mechanism is helpful to explore the tolerance of algae to abiotic stress. In another aspect, it will also provide the necessary theoretical basis for the freshwater pesticide technology.