title: CAPS1 regulates catecholamine loading of large dense-core vesicles.
abstract: CAPS1 is thought to play an essential role in mediating exocytosis from large dense-core vesicles (LDCVs). We generated CAPS1-deficient (KO) mice and studied exocytosis in a model system for Ca2+-dependent LDCV secretion, the adrenal chromaffin cell. Adult heterozygous CAPS1 KO cells display a gene dosage-dependent decrease of CAPS1 expression and a concomitant reduction in the number of docked vesicles and secretion. Embryonic homozygous CAPS1 KO cells show a strong reduction in the frequency of amperometrically detectable release events of transmitter-filled vesicles, while the total number of fusing vesicles, as judged by capacitance recordings or total internal reflection microscopy, remains unchanged. We conclude that CAPS1 is required for an essential step in the uptake or storage of catecholamines in LDCVs.
authors.affiliation: Max-Planck-Institut für Experimentelle Medizin, Abteilung Molekulare Neurobiologie, D-37075 Göttingen, Germany.
authors.forename: Dina
authors.initials: D
authors.lastname: Speidel
authors.forename: Cathrin E
authors.initials: CE
authors.lastname: Bruederle
authors.forename: Carsten
authors.initials: C
authors.lastname: Enk
authors.forename: Thomas
authors.initials: T
authors.lastname: Voets
authors.forename: Frederique
authors.initials: F
authors.lastname: Varoqueaux
authors.forename: Kerstin
authors.initials: K
authors.lastname: Reim
authors.forename: Ute
authors.initials: U
authors.lastname: Becherer
authors.forename: Francesco
authors.initials: F
authors.lastname: Fornai
authors.forename: Stefano
authors.initials: S
authors.lastname: Ruggieri
authors.forename: Yvonne
authors.initials: Y
authors.lastname: Holighaus
authors.forename: Eberhard
authors.initials: E
authors.lastname: Weihe
authors.forename: Dieter
authors.initials: D
authors.lastname: Bruns
authors.forename: Nils
authors.initials: N
authors.lastname: Brose
authors.forename: Jens
authors.initials: J
authors.lastname: Rettig
mesh_terms: D000818:Animals; D015153:Blotting, Western; D001921:Brain / Q000196:embryology / Q000254:growth & development / Q000378:metabolism; D002135:Calcium-Binding Proteins / Q000172:deficiency / Q000235:genetics / Q000378:metabolism*; D002395:Catecholamines / Q000378:metabolism*; D002478:Cells, Cultured; D004622:Embryo, Mammalian; D005089:Exocytosis / Q000502:physiology; D051379:Mice; D018345:Mice, Knockout; D046529:Microscopy, Electron, Transmission; D009419:Nerve Tissue Proteins / Q000172:deficiency / Q000235:genetics / Q000378:metabolism*; D009474:Neurons / Q000378:metabolism* / Q000648:ultrastructure; D018408:Patch-Clamp Techniques; D022142:Secretory Vesicles / Q000502:physiology*
chemical_list: D002135:Calcium-Binding Proteins; D002395:Catecholamines; D009419:Nerve Tissue Proteins