3BBZ

Structure of the nucleocapsid-binding domain from the mumps virus phosphoprotein

Summary for 3BBZ

• Entry DOI: 10.2210/pdb3bbz/pdb
• Descriptor: P protein, BROMIDE ION, FORMIC ACID, ... (4 entities in total)
• Functional Keywords: molten globule, viral protein, replication
• Biological source: Mumps virus
• Total number of polymer chains: 2
• Total formula weight: 11346.63

Authors

Kingston, R.L.,Gay, L.S.,Baase, W.S.,Matthews, B.W. (deposition date: 2007-11-11, release date: 2008-05-27, Last modification date: 2024-05-29)

Primary citation

Kingston, R.L.,Gay, L.S.,Baase, W.S.,Matthews, B.W.
Structure of the nucleocapsid-binding domain from the mumps virus polymerase; an example of protein folding induced by crystallization
J.Mol.Biol., 379:719-731, 2008

PubMed Abstract: The human pathogen mumps virus, like all paramyxoviruses, encodes a polymerase responsible for virally directed RNA synthesis. The template for the polymerase is the nucleocapsid, a filamentous protein-RNA complex harboring the viral genome. Interaction of the polymerase and the nucleocapsid is mediated by a small domain tethered to the end of the phosphoprotein (P), one of the polymerase subunits. We report the X-ray crystal structure of this region of mumps virus P (the nucleocapsid-binding domain, or NBD, amino acids 343-391). The mumps P NBD forms a compact bundle of three alpha-helices within the crystal, a fold apparently conserved across the Paramyxovirinae. In solution, however, the domain exists in the molten globule state. This is demonstrated through application of differential scanning calorimetry, circular dichroism spectroscopy, NMR spectroscopy, and dynamic light scattering. While the mumps P NBD is compact and has persistent secondary structure, it lacks a well-defined tertiary structure under normal solution conditions. It can, however, be induced to fold by addition of a stabilizing methylamine cosolute. The domain provides a rare example of a molten globule that can be crystallized. The structure that is stabilized in the crystal represents the fully folded state of the domain, which must be transiently realized during binding to the viral nucleocapsid. While the intermolecular forces that govern the polymerase-nucleocapsid interaction appear to be different in measles, mumps, and Sendai viruses, for each of these viruses, polymerase translocation involves the coupled binding and folding of protein domains. In all cases, we suggest that this will result in a weak-affinity protein complex with a short lifetime, which allows the polymerase to take rapid steps forward.

PubMed: 18468621
DOI: 10.1016/j.jmb.2007.12.080

Experimental method

X-RAY DIFFRACTION (2.1 Å)