title: Localization of phospholipid-binding sites of caldesmon.
abstract: The interaction of phosphatidylserine with intact smooth muscle caldesmon and caldesmon fragments obtained by bacterial expression was investigated by means of light scattering. Among these fragments only those derived from the C-terminal part of caldesmon (so-called domain 4) were able to interact with phospholipids. Fragments 606C (residues 606-756), H7 (566-710) and H2 (626-710) form tight complexes with phosphatidylserine, whereas fragments H8 (658-737), H9 (669-737) and fragment H4 (566-624) interact with phospholipids less effectively. It is concluded that the phospholipid-binding site is located in the sequence 626-710 of caldesmon. This sequence contains calmodulin-binding sites and serine residues phosphorylated by protein kinase C and pro-directed protein kinases. This could explain the effects of calmodulin and phosphorylation on the caldesmon-phospholipid interaction described earlier.
authors.affiliation: Department of Biochemistry, School of Biology, Moscow State University, Russian Federation.
authors.forename: N V
authors.initials: NV
authors.lastname: Bogatcheva
authors.forename: P A
authors.initials: PA
authors.lastname: Huber
authors.forename: I D
authors.initials: ID
authors.lastname: Fraser
authors.forename: S B
authors.initials: SB
authors.lastname: Marston
authors.forename: N B
authors.initials: NB
authors.lastname: Gusev
mesh_terms: D000199:Actins / Q000378:metabolism; D000595:Amino Acid Sequence; D000818:Animals; D001665:Binding Sites; D002147:Calmodulin / Q000378:metabolism; D002148:Calmodulin-Binding Proteins / Q000737:chemistry / Q000378:metabolism*; D002417:Cattle; D002645:Chickens; D004372:Ducks; D006801:Humans; D066298:In Vitro Techniques; D008027:Light; D015394:Molecular Structure; D010446:Peptide Fragments / Q000737:chemistry / Q000378:metabolism; D010743:Phospholipids / Q000378:metabolism*; D012542:Scattering, Radiation
chemical_list: D000199:Actins; D002147:Calmodulin; D002148:Calmodulin-Binding Proteins; D010446:Peptide Fragments; D010743:Phospholipids