Protein Science, Vol 7, Issue 11 2265-2280, Copyright © 1998 by Cold Spring Harbor Laboratory Press

ARTICLE

Solution structure and backbone dynamics of Mason-Pfizer monkey virus (MPMV) nucleocapsid protein

Y. GAO, K. KALUARACHCHI and D. P. GIEDROC
Center for Macromolecular Design, Department of Biochemistry and Biophysics, Texas A&M University, College Station, Texas 77843-2128

Retroviral nucleocapsid proteins (NCPs) are CCHC-type zinc finger proteins that mediate virion RNA binding activities associated with retrovirus assembly and genomic RNA encapsidation. Mason-Pfizer monkey virus (MPMV), a type D retrovirus, encodes a 96-amino acid nucleocapsid protein, which contains two Cys-X(2)-Cys-X(4)-His-X(4)-Cys (CCHC) zinc fingers connected by an unusually long 15-amino acid linker. Homonuclear, two-dimensional sensitivity-enhanced (15)N-(1)H, three-dimensional (15)N-(1)H, and triple resonance NMR spectroscopy have been used to determine the solution structure and residue-specific backbone dynamics of the structured core domain of MPMV NCP containing residues 21-80. Structure calculations and spectral density mapping of N-H bond vector mobility reveal that MPMV NCP 21-80 is best described as two independently folded, rotationally uncorrelated globular domains connected by a seven-residue flexible linker consisting of residues 42-48. The N-terminal CCHC zinc finger domain (residues 24-37) appears to adopt a fold like that described previously for HIV-1 NCP; however, residues within this domain and the immediately adjacent linker region (residues 38-41) are characterized by extensive conformational averaging on the {mu}s-ms time scale at 25{deg}C. In contrast to other NCPs, residues 49-77, which includes the C-terminal CCHC zinc-finger (residues 53-66), comprise a well-folded globular domain with the Val49-Pro-Gly-Leu52 sequence and C-terminal tail residues 67-77 characterized by amide proton exchange properties and (15)N R(1), R(2), and {(1)H-(15)N} NOE values indistinguishable to residues in the core C-terminal finger. Twelve refined structural models of MPMV NCP residues 49-80 (pairwise backbone RMSD of 0.77 A) reveal that the side chains of the conserved Pro50 and Trp62 are in van der Waals contact with one another. Residues 70-73 in the C-terminal tail adopt a reverse turn-like structure. Ile77 is involved in extensive van der Waals contact with the core finger domain, while the side chains of Ser68 and Asn75 appear to form hydrogen bonds that stabilize the overall fold of this domain. These residues outside of the core finger structure are conserved in D-type and related retroviral NCPs, e.g., MMTV NCP, suggesting that the structure of MPMV NCP may be representative of this subclass of retroviral NCPs.
CiteULike    Connotea    Del.icio.us    Digg    Reddit    Technorati    What's this?

This article has been cited by other articles:

				V. Nemeth-Pongracz, O. Barabas, M. Fuxreiter, I. Simon, I. Pichova, M. Rumlova, H. Zabranska, D. Svergun, M. Petoukhov, V. Harmat, et al. Flexible segments modulate co-folding of dUTPase and nucleocapsid proteins Nucleic Acids Res., January 28, 2007; 35(2): 495 - 505. [Abstract] [Full Text] [PDF]

				P. Ulbrich, S. Haubova, M. V. Nermut, E. Hunter, M. Rumlova, and T. Ruml Distinct Roles for Nucleic Acid in In Vitro Assembly of Purified Mason-Pfizer Monkey Virus CANC Proteins J. Virol., July 15, 2006; 80(14): 7089 - 7099. [Abstract] [Full Text] [PDF]

				I. Onn, N. Milman-Shtepel, and J. Shlomai Redox Potential Regulates Binding of Universal Minicircle Sequence Binding Protein at the Kinetoplast DNA Replication Origin Eukaryot. Cell, April 1, 2004; 3(2): 277 - 287. [Abstract] [Full Text] [PDF]

				O. Barabas, M. Rumlova, A. Erdei, V. Pongracz, I. Pichova, and B. G. Vertessy dUTPase and Nucleocapsid Polypeptides of the Mason-Pfizer Monkey Virus Form a Fusion Protein in the Virion with Homotrimeric Organization and Low Catalytic Efficiency J. Biol. Chem., October 3, 2003; 278(40): 38803 - 38812. [Abstract] [Full Text] [PDF]

				Y. M. Ma and V. M. Vogt Rous Sarcoma Virus Gag Protein-Oligonucleotide Interaction Suggests a Critical Role for Protein Dimer Formation in Assembly J. Virol., May 3, 2002; 76(11): 5452 - 5462. [Abstract] [Full Text] [PDF]

				K.-i. Takahashi, S. Baba, Y. Koyanagi, N. Yamamoto, H. Takaku, and G. Kawai Two Basic Regions of NCp7 Are Sufficient for Conformational Conversion of HIV-1 Dimerization Initiation Site from Kissing-loop Dimer to Extended-duplex Dimer J. Biol. Chem., August 10, 2001; 276(33): 31274 - 31278. [Abstract] [Full Text] [PDF]