Chikungunya is a mosquito-borne disease characterized by a rapid onset of fever, followed by debilitating joint pains and arthritis that can last for months or years. The replication of the Alphavirus genome takes place in a virus-induced RNA replication organelle, also known as a ‘spherule’ or ‘replication complex.’ This organelle is formed as an outward-facing plasma membrane bud with a diameter of 50–80 nm. The size of the membrane bud has been shown to depend on the length of the viral genome. The bud is thought to have a stable, open neck that connects it to the cytoplasm, and this high-curvature membrane shape persists for several hours in the infected cell during active RNA production. The viral nsPs are thus thought to serve the additional role of maintaining this peculiar membrane shape while replicating the viral RNA.Within the core RNA replicase, the viral polymerase nsP4, which is in complex with nsP2 helicase-protease, sits in the central pore of the membrane-anchored nsP1 RNA-capping ring. The addition of a large cytoplasmic ring next to the C terminus of nsP1 forms the holo-RNA-RC as observed at the neck of spherules formed in virus-infected cells. Here you can see a cryEM structure of the whole Chikungunya virus replication complex (PDB code: 7Y38)
#molecularart ... #immolecular ..: #alphavirus ... #replication ... #complex ... #RNA ... #helicase ... #Chikungunya ... #cryoem
Structure rendered with @proteinimaging and depicted with @corelphotopaint
#molecularart ... #immolecular ..: #alphavirus ... #replication ... #complex ... #RNA ... #helicase ... #Chikungunya ... #cryoem
Structure rendered with @proteinimaging and depicted with @corelphotopaint
