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.
Majumdar
Amitabha
A
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.
Bhattacharya
Raja
R
Basak
Soumen
S
Shaila
M S
MS
Chattopadhyay
Dhrubajyoti
D
Roy
Siddhartha
S
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