title: Lipids implicated in the journey of a secretory granule: from biogenesis to fusion.
abstract: The regulated secretory pathway begins with the formation of secretory granules by budding from the Golgi apparatus and ends by their fusion with the plasma membrane leading to the release of their content into the extracellular space, generally following a rise in cytosolic calcium. Generation of these membrane-bound transport carriers can be classified into three steps: (i) cargo sorting that segregates the cargo from resident proteins of the Golgi apparatus, (ii) membrane budding that encloses the cargo and depends on the creation of appropriate membrane curvature, and (iii) membrane fission events allowing the nascent carrier to separate from the donor membrane. These secretory vesicles then mature as they are actively transported along microtubules toward the cortical actin network at the cell periphery. The final stage known as regulated exocytosis involves the docking and the priming of the mature granules, necessary for merging of vesicular and plasma membranes, and the subsequent partial or total release of the secretory vesicle content. Here, we review the latest evidence detailing the functional roles played by lipids during secretory granule biogenesis, recruitment, and exocytosis steps. In this review, we highlight evidence supporting the notion that lipids play important functions in secretory vesicle biogenesis, maturation, recruitment, and membrane fusion steps. These effects include regulating various protein distribution and activity, but also directly modulating membrane topology. The challenges ahead to understand the pleiotropic functions of lipids in a secretory granule's journey are also discussed. This article is part of a mini review series on Chromaffin cells (ISCCB Meeting, 2015).
authors.affiliation: Institut des Neurosciences Cellulaires et Intégratives (INCI), UPR-3212 Centre National de la Recherche Scientifique & Université de Strasbourg, Strasbourg, France.
authors.forename: Emeline
authors.initials: E
authors.lastname: Tanguy
authors.affiliation: INSERM U982, Laboratoire de Différenciation et Communication Neuronale et Neuroendocrine, Institut de Recherche et d'Innovation Biomédicale, Université de Rouen, Mont-Saint-Aignan, France.
authors.forename: Ophélie
authors.initials: O
authors.lastname: Carmon
authors.affiliation: Institut des Neurosciences Cellulaires et Intégratives (INCI), UPR-3212 Centre National de la Recherche Scientifique & Université de Strasbourg, Strasbourg, France.
authors.forename: Qili
authors.initials: Q
authors.lastname: Wang
authors.affiliation: INSERM U982, Laboratoire de Différenciation et Communication Neuronale et Neuroendocrine, Institut de Recherche et d'Innovation Biomédicale, Université de Rouen, Mont-Saint-Aignan, France.
authors.forename: Lydie
authors.initials: L
authors.lastname: Jeandel
authors.affiliation: Institut des Neurosciences Cellulaires et Intégratives (INCI), UPR-3212 Centre National de la Recherche Scientifique & Université de Strasbourg, Strasbourg, France.
authors.forename: Sylvette
authors.initials: S
authors.lastname: Chasserot-Golaz
authors.affiliation: INSERM U982, Laboratoire de Différenciation et Communication Neuronale et Neuroendocrine, Institut de Recherche et d'Innovation Biomédicale, Université de Rouen, Mont-Saint-Aignan, France.
authors.forename: Maité
authors.initials: M
authors.lastname: Montero-Hadjadje
authors.affiliation: Institut des Neurosciences Cellulaires et Intégratives (INCI), UPR-3212 Centre National de la Recherche Scientifique & Université de Strasbourg, Strasbourg, France.
authors.forename: Nicolas
authors.initials: N
authors.lastname: Vitale
mesh_terms: D000818:Animals; D001692:Biological Transport / Q000502:physiology; D002118:Calcium / Q000378:metabolism; D003594:Cytoplasmic Granules / Q000502:physiology*; D005089:Exocytosis / Q000502:physiology; D006801:Humans; D008055:Lipids / Q000502:physiology*; D008561:Membrane Fusion / Q000502:physiology*; D022142:Secretory Vesicles / Q000502:physiology*
chemical_list: D008055:Lipids; D002118:Calcium
keywords: exocytosis; lipid; membrane; microdomain; secretion; secretory granule budding