Gene Expression Profiles Analysis Of Tobacco In Response To Low Potassium Stress

Potassium is closely related to tobacco quality. It can improve the tobacco appearance quality,make tobacco full of elasticity, make tobacco identity moderately, improve combustibility and coordinate the chemical composition. In addition, tobacco as a kind of economic crops pleased potassium and soil available potassium content in the lower current situation there is a contradiction. Therefore, to explore tobacco related gene expression in response to low potassium, research on tobacco low potassium molecular response mechanism and providing genetic resources for tobacco breeding is the work currently carried out urgently. This study through the medium to cultivate tobacco seedlings K326, carried out Oh (control),6h,12h and 24h low potassium stress treatment, starting from the transcriptome level, using gene chip technology test and research the tobacco genes responsded in low potassium, used the time series trend analysis, heat map hotspots cluster analysis,pathway metabolic pathway analysis, GO functional classification for data mining. The results of the study are as follows:1,This study with Oh as a reference, comparative analysis of three different time points gene expression levels, statistic of the gene numbers about significant differences in expression (p value≤0.05)and the differential expression of multiple greater than 2-fold,we found a total of changes in non-redundant information 3790 differentially expressed genes, of which the first time 6h have largest number of differentially expressed genes and the most obvious response, the number of genes is 2277, up 1270, down 1007; 12h changes in gene number is 1954, up 1159, down 795; 24h changes in gene number is 1835, up 1,023, down 812. Three treatments have comme in differentially expressed genes are 300 up-regulated genes and 257 down-regulated genes, of which 557 genes involved in the expression of eight time-series trends.2, Metabolic pathway significant analysis(p value≤0.05) of Tobacco low potassium stress showed that:after each treatment genes(up/down) alone annotated, we significantly enriched to 49 metabolic pathways, including nitrogen metabolism, carotenoid biosynthesis, photosynthetic-antenna protein, photosynthetic carbon fixation, starch and sucrose metabolism, glycolysis/gluconeogenesis, pentose phosphate pathway, such as associated with important way to the formation of the yield and quality of tobacco.3, GO functional classification significant (p value≤0.05)analysis showed that: by low potassium stress,we significantly enriched to 18 GO (two categories), including antioxidant activity, structural molecule activity, electron carrier activity, response to stimulus, transporter activity, immune system process, localization, death, anatomical structure formation, enzyme regulator activity, developmental process, multicellular organismal process, catalytic activity, biological regulation, metabolic process, cellular process, transcription regulator activity, binding.4, In the present study, we found five potassium transporter genes, including KUP3, KUP6, KUPll, AtCHX13, SKOR. In transmembrane transporter activity, we found 130 DEGs, and related mineral ions have AMT, NRT, ACA, CAX, CNGC, ECA, PHT, SULTR, MGT, etc.; In response to abiotic stimuli we found 417 DEGs including ERF, HSF, GATA, etc.; In transcription factor activity we found 201 DEGs, including MYB, WRKY, bZIP, NAC, etc.; In nitrogen metabolism we found 152 DEGs, containing nitrate assimilation gene GAD, GSR, GDH, NIA, etc.; In cell wall structure we found 14 DEGs, including the structural protein genes EXT, LRX, EXP; biosynthesis found 704 DEGs, including photosynthetic pigment synthesis genes PSY, AT5G17230, LYC, BETA-OHASE etc.;In glucose metabolism we found 66 DEGs, including AtSPS, PHS, UGP, HKL, PGM, PFK, ALDH, AT5G56350, G6PD, etc.; In signal transduction we found 67 DEGs, including YUC, SAM, IPT, CAM, CBL, ANNAT, CBL, etc.; In respiratory burst we found 18 DEGs, most of which is ethylene response factor ERF; In aging we found 25 DEGs, including ATQ CPR5, SAG, etc.; In photosynthesis we found 25 DEGs, including LHCB, CAB, LHCA, AtNADP-ME, AT5G38420, AtPPC etc.5, Tobacco low potassium stress caused widespread molecular level changes, including metabolic pathways and functional classification who is closely related with tobacco quality, and enriched a large number of differentially expressed genes involved, analysising these genes function is beneficial to research the molecular response mechanism in tobacco low potassium stress.