title: Calcium-myristoyl switch, subcellular localization, and calcium-dependent translocation of the neuronal calcium sensor protein VILIP-3, and comparison with VILIP-1 in hippocampal neurons.
abstract: Neuronal calcium sensor (NCS) proteins including the subfamily of visinin-like-proteins (VILIPs) are involved in regulation of various signaling cascades. One molecular regulation mechanism is the calcium-myristoyl switch. VILIPs show a calcium-dependent membrane association in brain homogenates; however, differences in calcium-induced conformation changes and degree of membrane association are reported. Little is known about differences in the calcium-myristoyl switch in living cells leading to localization of VILIPs to distinct subcellular compartments. Therefore, we studied the calcium-dependent localization of green fluorescent protein (GFP)-tagged VILIP-3 in living cell lines and hippocampal neurons and compared it with that of GFP-VILIP-1. Interestingly, the observed fast and reversible calcium-myristoyl switch of VILIP-3-GFP and VILIP-1-GFP differed, e.g., in calcium-dependent translocation to Golgi membranes. Similarily, the calcium-dependent localization of endogenously expressed VILIP-3 and -1 in dendrites differed. Thus, VILIPs co-expressed in the same neuron show clear differences in calcium-dependent localization which may allow neurons a highly selective response to various calcium stimuli.
authors.affiliation: Signal Transduction Research Group, Neuroscience Research Center/Institute for Physiology of the Charite, Humboldt University Berlin, Tucholskystrasse 2, D-10117 Berlin, Germany.
authors.forename: Christina
authors.initials: C
authors.lastname: Spilker
authors.forename: Karl-Heinz
authors.initials: KH
authors.lastname: Braunewell
mesh_terms: D000818:Animals; D019556:COS Cells; D002118:Calcium / Q000378:metabolism; D020013:Calcium Signaling / Q000502:physiology*; D002135:Calcium-Binding Proteins / Q000378:metabolism*; D002451:Cell Compartmentation / Q000502:physiology; D002462:Cell Membrane / Q000378:metabolism; D003712:Dendrites / Q000378:metabolism; D005968:Glutamate Decarboxylase / Q000378:metabolism; D006056:Golgi Apparatus / Q000378:metabolism; D049452:Green Fluorescent Proteins; D006624:Hippocampus / Q000166:cytology / Q000378:metabolism*; D008164:Luminescent Proteins; D008565:Membrane Proteins / Q000378:metabolism; D051379:Mice; D008869:Microtubule-Associated Proteins / Q000378:metabolism; D019814:Myristic Acid / Q000378:metabolism; D009419:Nerve Tissue Proteins / Q000378:metabolism*; D051596:Neurocalcin; D009474:Neurons / Q000166:cytology / Q000378:metabolism*; D011189:Potassium Chloride / Q000494:pharmacology; D021381:Protein Transport / Q000502:physiology; D050765:Qa-SNARE Proteins; D051381:Rats; D044169:Receptors, Calcium-Sensing / Q000378:metabolism*; D017470:Receptors, Glutamate / Q000187:drug effects / Q000378:metabolism; D011993:Recombinant Fusion Proteins
chemical_list: D002135:Calcium-Binding Proteins; C469810:Hpcal1 protein, rat; D008164:Luminescent Proteins; D008565:Membrane Proteins; D008869:Microtubule-Associated Proteins; D009419:Nerve Tissue Proteins; D051596:Neurocalcin; D050765:Qa-SNARE Proteins; D044169:Receptors, Calcium-Sensing; D017470:Receptors, Glutamate; D011993:Recombinant Fusion Proteins; C496689:Vsnl1 protein, mouse; C496690:Vsnl1 protein, rat; D019814:Myristic Acid; D049452:Green Fluorescent Proteins; D011189:Potassium Chloride; D005968:Glutamate Decarboxylase; D002118:Calcium