title: Roles of three Fusarium oxysporum calcium ion (Ca(2+)) channels in generating Ca(2+) signatures and controlling growth.
abstract: Spatial and temporal changes of cytoplasmic calcium ions ([Ca(2+)]c), caused by external stimuli, are known as the Ca(2+) signature and presumably control cellular and developmental responses. Multiple types of ion channels, pumps, and transporters on plasma and organellar membranes modulate influx and efflux of Ca(2+) to and from the extracellular environment and internal Ca(2+) stores to form Ca(2+) signatures. Expression of a fluorescent protein-based Ca(2+) probe, Cameleon YC3.60, in Fusarium oxysporum enabled us to study how disruption of three Ca(2+) channel genes, including FoCCH1, FoMID1 and FoYVC1, affects Ca(2+) signature formation at polarized hyphal tips and whether specific changes in the Ca(2+) signature caused by these mutations are related to growth-related phenotypes. Resulting mutants displayed altered amplitude, interval, and duration of Ca(2+) pulses under various external Ca(2+) concentrations as well as changes in sporulation and growth. Loss of FoMID1 and FoCCH1, genes encoding putative plasma membrane channel proteins, had a major impact on Ca(2+) signatures and growth, while disruption of FoYVC1, which encodes a vacuolar channel, only subtly affected both traits. Results from our study provide new insights into the underpinning of Ca(2+) signaling in fungi and its role in controlling growth and also raise several new questions.
authors.affiliation: Department of Biological Sciences, University of Delaware, Newark, DE 19716, United States; Delaware Biotechnology Institute, Newark, DE 19711, United States.
authors.forename: Hye-Seon
authors.initials: HS
authors.lastname: Kim
authors.affiliation: Department of Plant Pathology & Environmental Microbiology, The Pennsylvania State University, University Park, PA 16802, United States.
authors.forename: Jung-Eun
authors.initials: JE
authors.lastname: Kim
authors.affiliation: Department of Biological Sciences, University of Delaware, Newark, DE 19716, United States.
authors.forename: Daniel
authors.initials: D
authors.lastname: Frailey
authors.affiliation: Department of Biological Sciences, University of Delaware, Newark, DE 19716, United States.
authors.forename: Anja
authors.initials: A
authors.lastname: Nohe
authors.affiliation: Department of Biological Sciences, University of Delaware, Newark, DE 19716, United States.
authors.forename: Randall
authors.initials: R
authors.lastname: Duncan
authors.affiliation: Department of Biological Sciences, University of Delaware, Newark, DE 19716, United States; Delaware Biotechnology Institute, Newark, DE 19711, United States. Electronic address: Kirk.Czymmek@zeiss.com.
authors.forename: Kirk J
authors.initials: KJ
authors.lastname: Czymmek
authors.affiliation: Department of Plant Pathology & Environmental Microbiology, The Pennsylvania State University, University Park, PA 16802, United States. Electronic address: sxk55@psu.edu.
authors.forename: Seogchan
authors.initials: S
authors.lastname: Kang
mesh_terms: D002118:Calcium / Q000378:metabolism*; D015220:Calcium Channels / Q000235:genetics* / Q000378:metabolism*; D020013:Calcium Signaling; D003470:Culture Media; D005670:Fusarium / Q000502:physiology*; D015870:Gene Expression; D025301:Hyphae; D009154:Mutation; D059008:Time-Lapse Imaging
chemical_list: D015220:Calcium Channels; D003470:Culture Media; D002118:Calcium
keywords: Calcium imaging; Calcium signaling; Calcium signature; Hyphal growth