title: Elemental propagation of calcium signals in response-specific patterns determined by environmental stimulus strength.
abstract: Plant cells can respond qualitatively and quantitatively to a wide range of environmental signals. Ca(2+) is used as an intracellular signal for volume regulation in response to external osmotic changes. We show here that the spatiotemporal patterns of hypo-osmotically induced Ca(2+) signals vary dramatically with stimulus strength in embryonic cells of the marine alga Fucus. Biphasic or multiphasic Ca(2+) signals reflect Ca(2+) elevations in distinct cellular domains. These propagate via elemental Ca(2+) release in nuclear or peripheral regions that are rich in endoplasmic reticulum. Cell volume regulation specifically requires Ca(2+) elevation in apical peripheral regions, whereas an altered cell division rate occurs only in response to stimuli that cause Ca(2+) elevation in nuclear regions.
authors.affiliation: Marine Biological Association of the United Kingdom, The Laboratory, Citadel Hill, Plymouth PL1 2PB, United Kingdom.
authors.forename: H
authors.initials: H
authors.lastname: Goddard
authors.forename: N F
authors.initials: NF
authors.lastname: Manison
authors.forename: D
authors.initials: D
authors.lastname: Tomos
authors.forename: C
authors.initials: C
authors.lastname: Brownlee
mesh_terms: D002118:Calcium / Q000378:metabolism*; D020013:Calcium Signaling; D002455:Cell Division; D048429:Cell Size; D002478:Cells, Cultured; D056890:Eukaryota / Q000254:growth & development / Q000378:metabolism*; D005456:Fluorescent Dyes; D015544:Inositol 1,4,5-Trisphosphate / Q000031:analogs & derivatives / Q000378:metabolism; D008027:Light; D018613:Microscopy, Confocal; D009930:Organic Chemicals; D009997:Osmotic Pressure; D014966:Xanthenes
chemical_list: D005456:Fluorescent Dyes; D009930:Organic Chemicals; D014966:Xanthenes; C061868:inositol 1,4,5-trisphosphate 1-(2-nitrophenyl)ethyl ester; C071336:calcium green; C034657:Texas red; D015544:Inositol 1,4,5-Trisphosphate; D002118:Calcium