title: Two-dimensional crystal structures of protein kinase C-delta, its regulatory domain, and the enzyme complexed with myelin basic protein.
abstract: Two-dimensional crystals of protein kinase C (PKC) delta, its regulatory domain (RDdelta), and the enzyme complexed with the substrate myelin basic protein have been grown on lipid monolayers composed of phosphatidylcholine: phosphatidylserine: diolein (45:50:5, molar ratio). Images have been reconstructed to 10-A resolution. The unit cells of all three proteins have cell edges a = b and interedge angle gamma = 60 degrees. RDdelta has an edge length of 33 +/- 1 A, and its reconstruction is donut shaped. The three-dimensional reconstructions from the PKCdelta C1b crystal structure () can be accommodated in this two-dimensional projection. Intact PKCdelta has an edge length of 46 +/- 1 A in the presence or absence of a nonhydrolyzable ATP analog, AMP-PnP. Its reconstruction has a similar donut shape, which can accommodate the C1b domain, but the spacing between donuts is greater than that in RDdelta; some additional structure is visible between the donuts. The complex of PKCdelta and myelin basic protein, with or without AMP-PnP, has an edge length of 43 +/- 1 A and a distinct structure. These results indicate that the C1 domains of RDdelta are tightly packed in the plane of the membrane in the two-dimensional crystals, that there is a single molecule of PKCdelta in the unit cell, and that its interaction with myelin basic protein induces a shift in conformation and/or packing of the enzyme.
authors.affiliation: Department of Anesthesiology, University of Virginia, Charlottesville, Virginia 22908, USA.
authors.forename: Alexander S
authors.initials: AS
authors.lastname: Solodukhin
authors.forename: Heather L
authors.initials: HL
authors.lastname: Caldwell
authors.forename: Julianne J
authors.initials: JJ
authors.lastname: Sando
authors.forename: Robert H
authors.initials: RH
authors.lastname: Kretsinger
mesh_terms: D000818:Animals; D001665:Binding Sites; D002460:Cell Line; D018360:Crystallography, X-Ray; D007527:Isoenzymes / Q000737:chemistry* / Q000648:ultrastructure; D008854:Microscopy, Electron; D004676:Myelin Basic Protein / Q000737:chemistry* / Q000648:ultrastructure; D011493:Protein Kinase C / Q000737:chemistry* / Q000648:ultrastructure; D051745:Protein Kinase C-delta; D011994:Recombinant Proteins / Q000737:chemistry / Q000648:ultrastructure; D018411:Spodoptera; D013499:Surface Properties; D014162:Transfection
chemical_list: D007527:Isoenzymes; D004676:Myelin Basic Protein; D011994:Recombinant Proteins; D011493:Protein Kinase C; D051745:Protein Kinase C-delta