P-protein of Chandipura virus is an N-protein-specific chaperone that acts at the nucleation stage.
The nucleocapsid protein N of Chandipura virus is prone to aggregation in vitro. We have shown that this aggregation occurs in two phases in a nucleation-dependent manner. Electron microscopy suggests that the aggregated state may have a ring-like structure. Using a GFP fusion, we have shown that the N-protein also aggregates in vivo. The P-protein suppresses the N-protein aggregation efficiently, both in vitro and in vivo. Increased lag phase in the presence of the P-protein suggests that chaperone-like action of the P-protein occurs before the nucleation event. The P-protein, however, does not exert any chaperone-like action against other proteins, suggesting that it binds to the N-protein specifically. Surface plasmon resonance and fluorescence enhancement indeed suggest that the P-protein binds tightly to the native N-protein. The P-protein is thus an N-protein-specific chaperone which inhibits the nucleation phase of N-protein aggregation, thus keeping a pool of encapsidation-competent N-protein for viral maturation.
Dr. B. C. Guha Centre for Genetic Engineering and Biotechnology, Department of Biochemistry, University College of Science, University of Calcutta, 35 Ballygunge Circular Road, Calcutta 700 019, India.
Amitabha
A
Majumdar
Raja
R
Bhattacharya
Soumen
S
Basak
M S
MS
Shaila
Dhrubajyoti
D
Chattopadhyay
Siddhartha
S
Roy
D000998:Antiviral Agents / Q000737:chemistry / Q000378:metabolism / Q000502:physiology*; D006367:HeLa Cells; D006801:Humans; D018832:Molecular Chaperones / Q000737:chemistry / Q000502:physiology* / Q000648:ultrastructure; D019590:Nucleocapsid Proteins / Q000037:antagonists & inhibitors* / Q000737:chemistry / Q000378:metabolism / Q000648:ultrastructure; D010750:Phosphoproteins / Q000737:chemistry / Q000378:metabolism / Q000502:physiology* / Q000648:ultrastructure; D010766:Phosphorylation; D011485:Protein Binding / Q000502:physiology; D018116:Vesiculovirus / Q000737:chemistry* / Q000502:physiology / Q000648:ultrastructure; D015678:Viral Structural Proteins / Q000737:chemistry / Q000378:metabolism / Q000502:physiology* / Q000648:ultrastructure; D019065:Virus Assembly / Q000502:physiology*
D000998:Antiviral Agents; D018832:Molecular Chaperones; D019590:Nucleocapsid Proteins; C412837:P protein, Chandipura virus; D010750:Phosphoproteins; D015678:Viral Structural Proteins