Proteomics Analysis In Suspension Cells Of Helianthus Tuberosus In Response To Salt Stress

Helianthus tuberosus is an herbaceous plant belongs to Helianthus of Compositae,has strong ecological adaptability,which easily grown in average,dry to medium moisture,well-drained soils in full sun to part shade and can grow in nutritionally poor or saline-alkaline soil.It grows naturally on moderately saline-alkali soil.Studies on the physiology of salt-tolerance of H.tuberosus mainly focus on leaves and tubers,few about the suspension cells.The research measured some physiologyical index including biomass,cell viability,antioxidase activities,the content of malondialdehyde(MDA),hydrogen peroxide(H2O2),proline,soluble proteins,soluble sugar and phenolics,in H.tuberosus under the treatment of 0,50,100,150,200 mmol·L-1NaCl.Based on that,the suspension cells of H.tuberosus that were treated with 150 mmol·L-1NaCl solution,were analyzed the changes of proteome with the Tandem Mass Tag(TMT)quantitative proteomics techniques.The result show that salt stress inhibited the cell activity and growth,made the increase of H2O2 and MDA content in H.tuberosus suspension cells.Osmotic adjustment substances were up-regulated induced by salt stress.The activity of ascorbate peroxidase and peroxidase enhanced significantly,the content of phenolics obviously increased to response to oxidative stress.In total,6231 proteins were identified in H.tuberosus suspension cells.A significantly changed protein was defined with FC>2 or FC<0.5 and p-value smaller than 0.05.Here,313 up-regulated expressed proteins and 365 down-regulated expressed proteins were further used in differentially expressed proteins analysis.Functional classification was produced with Uniprot,Gene Ontology and literature report.Up-regulated expressed proteins were divided into 10 groups,including secondary metabolism,oxidation-reduction process,stress and defense,tranport,protein synthesis and degradation,cellular organization,amino acid metabolism,fatty acid metabolism,signal trasduction and others,among them secondary metabolism-related proteins account for the largest proportion(35.1%).Down-regulated expressed proteins were classcified into 14 categories,containing biosynthesis and degradation of proteins,tranport,stress and defense,nucleotide metabolism,regulation of transcription,regulation of growth and cell division,cellular organization,cellular organization,oxidation-reduction process,lipid metabolism,binding,signal trasduction,secondary metabolism,protein localization and others.Draw the conclusion,salt stress inhibit the expression of cellar organization,repulication,groth and cell division-related proteins.Abundant proteins about the phenolic metabolism were notably up-regulated.Phenols have strong antioxidant activity,might play an important role in the process of H.-tuberosus suspension cells against oxidative stress caused by salt stress.