title: Lamination and spherulite-like compaction of a hormone's native amyloid-like nanofibrils: spectroscopic insights into key interactions.
abstract: The native hierarchical self-assembly process of natural somatostatin-14, a highly aromatic and charged peptide hormone involved in various inhibitory functions, was investigated mainly using vibrational spectroscopy (ATR-FTIR and Raman scattering) combined with electron microscopy. Generic kinetic features of amyloid fibrillogenesis were confirmed for the somatostatin-14 case, together with new insights into key interactions involved in the further hierarchical assembly of the somatostatin-14 nanofibrils into i) laterally associated nanofibers and ii) spherulite-like amyloid droplets resulting from the compaction of the nanofibers. In particular, the key role of aromatic side-chains in both fibrillogenesis and the association of the nanofibrils into higher order structures could be followed. It is proposed that the compaction propensity of the somatostatin-14 nanofibrils is relevant to the current hypothesis of the biological function of hormone self-assembly processes: hormone storage inside secretory granules.
authors.forename: Wilmar
authors.initials: W
authors.lastname: van Grondelle
authors.forename: Sophie
authors.initials: S
authors.lastname: Lecomte
authors.forename: Carmen
authors.initials: C
authors.lastname: Lopez-Iglesias
authors.forename: Jose-Maria
authors.initials: JM
authors.lastname: Manero
authors.forename: Roland
authors.initials: R
authors.lastname: Cherif-Cheikh
authors.forename: Maité
authors.initials: M
authors.lastname: Paternostre
authors.forename: Céline
authors.initials: C
authors.lastname: Valéry
mesh_terms: D000595:Amino Acid Sequence; D000682:Amyloid / Q000737:chemistry*; D006728:Hormones / Q000737:chemistry*; D008855:Microscopy, Electron, Scanning; D008969:Molecular Sequence Data; D057139:Nanofibers; D013057:Spectrum Analysis / Q000379:methods
chemical_list: D000682:Amyloid; D006728:Hormones