title: STIM1 translocation to the plasma membrane enhances intestinal epithelial restitution by inducing TRPC1-mediated Ca2+ signaling after wounding.
abstract: Early epithelial restitution is an important repair modality in the gut mucosa and occurs as a consequence of epithelial cell migration. Canonical transient receptor potential-1 (TRPC1) functions as a store-operated Ca2+ channel (SOCs) in intestinal epithelial cells (IECs) and regulates intestinal restitution, but the exact upstream signals initiating TRPC1 activation after mucosal injury remain elusive. Stromal interaction molecule 1 (STIM1) is a single membrane-spanning protein and is recently identified as essential components of SOC activation. The current study was performed to determine whether STIM1 plays a role in the regulation of intestinal epithelial restitution by activating TRPC1 channels. STIM1 translocation to the plasma membrane increased after wounding, which was followed by an increase in IEC migration to reseal wounds. Increased STIM1 levels at the plasma membrane by overexpressing EF-hand mutant STIM1 enhanced Ca2+ influx through SOCs and stimulated IEC migration after wounding. STIM1 interacted with TRPC1 and formed STIM1/TRPC1 complex, whereas inactivation of STIM1 by STIM1 silencing decreased SOC-mediated Ca2+ influx and inhibited epithelial restitution. In cells overexpressing EF-hand mutant STIM1, TRPC1 silencing also decreased STIM1/TRPC1 complex, reduced SOC-mediated Ca2+ influx, and repressed cell migration after wounding. Our findings demonstrate that induced STIM1 translocation to the plasma membrane promotes IEC migration after wounding by enhancing TRPC1-mediated Ca2+ signaling and provide new insight into the mechanism of intestinal epithelial restitution.
authors.affiliation: Cell Biology Group, Department of Surgery, University of Maryland School of Medicine, Baltimore, Maryland, USA.
authors.forename: Jaladanki N
authors.initials: JN
authors.lastname: Rao
authors.forename: Navneeta
authors.initials: N
authors.lastname: Rathor
authors.forename: Tongtong
authors.initials: T
authors.lastname: Zou
authors.forename: Lan
authors.initials: L
authors.lastname: Liu
authors.forename: Lan
authors.initials: L
authors.lastname: Xiao
authors.forename: Ting-Xi
authors.initials: TX
authors.lastname: Yu
authors.forename: Yu-Hong
authors.initials: YH
authors.lastname: Cui
authors.forename: Jian-Ying
authors.initials: JY
authors.lastname: Wang
mesh_terms: D000818:Animals; D002118:Calcium / Q000378:metabolism; D015220:Calcium Channels / Q000502:physiology; D020013:Calcium Signaling; D002460:Cell Line; D002462:Cell Membrane / Q000378:metabolism*; D002465:Cell Movement; D029721:Drosophila Proteins / Q000235:genetics / Q000378:metabolism*; D004847:Epithelial Cells / Q000502:physiology*; D007413:Intestinal Mucosa / Q000166:cytology / Q000293:injuries / Q000502:physiology*; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism*; D021381:Protein Transport; D051381:Rats; D000071737:Stromal Interaction Molecule 1; D050052:TRPC Cation Channels / Q000502:physiology*; D014945:Wound Healing
chemical_list: D015220:Calcium Channels; D029721:Drosophila Proteins; D008565:Membrane Proteins; C502662:Stim protein, Drosophila; D000071737:Stromal Interaction Molecule 1; D050052:TRPC Cation Channels; C096351:transient receptor potential cation channel, subfamily C, member 1; D002118:Calcium