title: Relationship between AtPase activity and conjugated polyamines in mitochondrial membrane from wheat seedling roots under osmotic stress.
abstract: The effects of osmotic stress on the ATPase activity, the contents of -SH group and conjugated polyamines in mitochondrial membrane from wheat seedling [Triticum aestivum L. cv. Yumai No. 18 (drought-tolerant) and cv. Yumai No. 9 (drought-sensitive)] roots were investigated. The results showed that ATPase activity and -SH group content decreased with polyethylene glycol(PEG) 6000(-0.55 MPa) treatment for 7 d, in concert with the decrease of the ratio of noncovalently conjugated spermidine (NCC-Spd)/noncovalently conjugated putrescine(NCC-Put) and increase of the covalently conjugated putrescine (CC-Put). Osmotic stress injury to Yangmai No.9 seedlings was alleviated greatly with 1 mmol/L exogenous spermidine(Spd), in concert with marked increases of the ratio of NCC-Spd/NCC-Put, -SH group contents and ATPase activity in mitochondrial membrane. Under osmotic stress, the concomitant treatment of Yumai No. 18 seedlings with methylglyoxyl bis(guanylhydrazone) (MGBG), an inhibitor of S-adenosyl methionine decarboxylase(SAMDC), and phenanthrolin (o-Phen), an inhibitor of transglutaminase(TGase), caused a significant decrease of the ratio of NCC-Spd/NCC-Put, CC-Put contents, respectively, in concert with the marked decreases of ATPase activity, -SH group content and its tolerance to osmotic stress. All the results above suggested that osmotic stress tolerance of wheat seedlings was associated with the ATPase activity, the contents of -SH group, NCC-Spd and CC-Put in mitochondrial membrane.
authors.affiliation: Key Laboratory of Crop Growth Regulation, Ministry of Agriculture, College of Life Science, Nanjing Agriculture University, Nanjing 210095, China. zwslsh@publicl.ptt.js.cn
authors.forename: Huai-Pan
authors.initials: HP
authors.lastname: Liu
authors.forename: Jun
authors.initials: J
authors.lastname: Liu
authors.forename: Yan-Yan
authors.initials: YY
authors.lastname: Zhang
authors.forename: You-Liang
authors.initials: YL
authors.lastname: Liu
mesh_terms: D000251:Adenosine Triphosphatases / Q000378:metabolism*; D015317:Biogenic Polyamines / Q000378:metabolism*; D007425:Intracellular Membranes / Q000378:metabolism*; D008565:Membrane Proteins / Q000378:metabolism; D008928:Mitochondria / Q000378:metabolism*; D009995:Osmosis / Q000502:physiology; D010472:Perchlorates; D018517:Plant Roots / Q000201:enzymology / Q000378:metabolism*; D013045:Species Specificity; D014908:Triticum / Q000201:enzymology / Q000378:metabolism*
chemical_list: D015317:Biogenic Polyamines; D008565:Membrane Proteins; D010472:Perchlorates; D000251:Adenosine Triphosphatases