title: Unraveling STIM2 function.
abstract: The discovery of molecular players in capacitative calcium (Ca(2+)) entry, also referred to as store-operated Ca(2+) entry (SOCE), supposed a great advance in the knowledge of cellular mechanisms of Ca(2+) entry, which are essential for a broad range of cellular functions. The identification of STIM1 and STIM2 proteins as the sensors of Ca(2+) stored in the endoplasmic reticulum unraveled the mechanism by which depletion of intracellular Ca(2+) stores is communicated to store-operated Ca(2+) channels located in the plasma membrane, triggering the activation of SOCE and intracellular Ca(2+)-dependent signaling cascades. Initial studies suggested a dominant function of STIM1 in SOCE and SOCE-dependent cellular functions compared to STIM2, especially those that participate in immune responses. Consequently, most of the subsequent studies focused on STIM1. However, during the last years, STIM2 has been demonstrated to play a more relevant and complex function than initially reported, being even important to sustain normal life in mice. These studies have led to reconsider the role of STIM2 in SOCE and its relevance in cellular physiology. This review is intended to summarize and provide an overview of the current data available about this exciting isoform, STIM2, and its actual position together with STIM1 in the mechanism of SOCE.
authors.affiliation: Department of Physiology (Cellular Physiology Research Group), University of Extremadura, Av. Universidad s/n, 10003, Cáceres, Spain.
authors.forename: Esther
authors.initials: E
authors.lastname: López
authors.forename: Ginés M
authors.initials: GM
authors.lastname: Salido
authors.forename: Juan A
authors.initials: JA
authors.lastname: Rosado
authors.forename: Alejandro
authors.initials: A
authors.lastname: Berna-Erro
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D002118:Calcium / Q000378:metabolism; D015220:Calcium Channels / Q000378:metabolism / Q000502:physiology; D020013:Calcium Signaling; D015815:Cell Adhesion Molecules / Q000737:chemistry / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D004721:Endoplasmic Reticulum / Q000378:metabolism; D015870:Gene Expression; D006801:Humans; D008969:Molecular Sequence Data; D020033:Protein Isoforms / Q000737:chemistry / Q000235:genetics / Q000378:metabolism / Q000502:physiology; D055550:Protein Stability; D017434:Protein Structure, Tertiary; D000071738:Stromal Interaction Molecule 2
chemical_list: D015220:Calcium Channels; D015815:Cell Adhesion Molecules; D020033:Protein Isoforms; C513279:STIM2 protein, human; D000071738:Stromal Interaction Molecule 2; D002118:Calcium