Closterovirus encoded HSP70 homolog and p61 in addition to both coat proteins function in efficient virion assembly.

@article{Satyanarayana2000ClosterovirusEH,
  title={Closterovirus encoded HSP70 homolog and p61 in addition to both coat proteins function in efficient virion assembly.},
  author={Tatineni Satyanarayana and Siddarame Gowda and Munir Mawassi and M R Albiach-Mart{\'i} and Mar{\'i}a A. Ayll{\'o}n and Cecile J. Robertson and Stephen M. Garnsey and William O. Dawson},
  journal={Virology},
  year={2000},
  volume={278 1},
  pages={
          253-65
        }
}
Assembly of the viral genome into virions is a critical process of the virus life cycle often defining the ability of the virus to move within the plant and to be transmitted horizontally to other plants. Closteroviridae virions are polar helical rods assembled primarily by a major coat protein, but with a related minor coat protein at one end. The Closteroviridae is the only virus family that encodes a protein with similarity to cellular chaperones, a 70-kDa heat-shock protein homolog (HSP70h… 

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TLDR
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TLDR
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Chaperone-mediated in vitro assembly of Polyomavirus capsids

TLDR
Polyomavirus capsid assembly can be recapitulated with high-fidelity in vitro using either prokaryotic or eukaryotic hsp70 chaperone systems, thereby supporting a role for cellular chaperones in the in vivo regulation of virion assembly.
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