title: Signaling role of phospholipid hydroperoxide glutathione peroxidase (PHGPX) accompanying sensing of NaCl stress in etiolated sunflower seedling cotyledons.
abstract: Sunflower seedlings subjected to 120 mM NaCl stress exhibit high total peroxidase activity, differential expression of its isoforms and accumulation of lipid hydroperoxides. This coincides with high specific activity of phospholipid hydroperoxide glutathione peroxidase (PHGPX) in the 10,000g supernatant from the homogenates of 2-6 d old seedling cotyledons. An upregulation of PHGPX activity by NaCl is evident from Western blot analysis. Confocal laser scanning microscopic (CLSM) analysis of sections of cotyledons incubated with anti-GPX4 (PHGPX) antibody highlights an enhanced cytosolic accumulation of PHGPX, particularly around the secretory canals. Present work, thus, highlights sensing of NaCl stress in sunflower seedlings in relation with lipid hydroperoxide accumulation and its scavenging through an upregulation of PHGPX activity in the cotyledons.
authors.affiliation: a Laboratory of Plant Physiology and Biochemistry; Department of Botany; University of Delhi ; Delhi , India.
authors.forename: Prachi
authors.initials: P
authors.lastname: Jain
authors.forename: Satish C
authors.initials: SC
authors.lastname: Bhatla
mesh_terms: D018548:Cotyledon / Q000187:drug effects / Q000502:physiology*; D064527:Etiolation / Q000187:drug effects*; D005979:Glutathione Peroxidase / Q000378:metabolism*; D006368:Helianthus / Q000187:drug effects / Q000201:enzymology / Q000502:physiology; D000080662:Phospholipid Hydroperoxide Glutathione Peroxidase; D010940:Plant Proteins / Q000378:metabolism; D036226:Seedlings / Q000187:drug effects / Q000502:physiology*; D015398:Signal Transduction / Q000187:drug effects*; D012965:Sodium Chloride / Q000494:pharmacology*; D012995:Solubility; D013312:Stress, Physiological / Q000187:drug effects*
chemical_list: D010940:Plant Proteins; D012965:Sodium Chloride; D000080662:Phospholipid Hydroperoxide Glutathione Peroxidase; D005979:Glutathione Peroxidase
keywords: CLSM, confocal laser scanning microscopy; GPX, glutathione peroxidase; LHPO, lipid hydroperoxide; PHGPX, phospholipid hydroperoxide glutathione peroxidase; POD,peroxidase; ROS, reactive oxygen species.; glutathione peroxidase; lipid hydroperoxides; phospholipid hydroperoxide glutathione peroxidase; salt stress; seedling cotyledons; sunflower