title: Structure-function analysis of the filamentous actin binding domain of the neuronal scaffolding protein spinophilin.
abstract: Spinophilin, a neuronal scaffolding protein, is essential for synaptic transmission, and functions to target protein phosphatase-1 to distinct subcellular locations in dendritic spines. It is vital for the regulation of dendritic spine formation and motility, and functions by regulating glutamatergic receptors and binding to filamentous actin. To investigate its role in regulating actin cytoskeletal structure, we initiated structural studies of the actin binding domain of spinophilin. We demonstrate that the spinophilin actin binding domain is intrinsically unstructured, and that, with increasing C-terminal length, the domain shows augmented secondary structure content. Further characterization confirmed the previously known crosslinking activity and uncovered a novel filamentous actin pointed-end capping activity. Both of these functions seem to be fully contained within residues 1-154 of spinophilin.
authors.affiliation: Max Delbrück Center for Molecular Medicine, Berlin-Buch, Germany. herwig.schueler@med.uni-heidelberg.de
authors.forename: Herwig
authors.initials: H
authors.lastname: Schüler
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Peti
mesh_terms: D000818:Animals; D002942:Circular Dichroism; D003001:Cloning, Molecular; D008840:Microfilament Proteins / Q000737:chemistry* / Q000378:metabolism*; D009419:Nerve Tissue Proteins / Q000737:chemistry* / Q000378:metabolism*; D019906:Nuclear Magnetic Resonance, Biomolecular; D017433:Protein Structure, Secondary; D017434:Protein Structure, Tertiary; D051381:Rats; D013329:Structure-Activity Relationship; D000099273:Neurabins
chemical_list: D008840:Microfilament Proteins; D009419:Nerve Tissue Proteins; D000099273:Neurabins