Structural highlights
Function
CAPSD_BPPP7 Capsid protein self-assembles to form an icosahedral capsid with a T=3 symmetry, about 26 nm in diameter, and consisting of 89 capsid proteins dimers (178 capsid proteins) (PubMed:10739912). Involved in viral genome encapsidation through the interaction between a capsid protein dimer and the multiple packaging signals present in the RNA genome (By similarity).[UniProtKB:P03612][1] Acts as a translational repressor of viral replicase synthesis late in infection. This latter function is the result of capsid protein interaction with an RNA hairpin which contains the replicase ribosome-binding site.[2]
Publication Abstract from PubMed
As self-assembling polyvalent nanoscale structures that can tolerate substantial genetic and chemical modification, virus-like particles are useful in a variety of fields. Here we describe the genetic modification and structural characterization of the Leviviridae PP7 capsid protein as a platform for the presentation of functional polypeptides. This particle was shown to tolerate the display of sequences from 1 kDa (a cell penetrating peptide) to 14 kDa (the Fc-binding double Z-domain) on its exterior surface as C-terminal genetic fusions to the coat protein. In addition, a dimeric construct allowed the presentation of exogenous loops between capsid monomers and the simultaneous presentation of two different peptides at different positions on the icosahedral structure. The PP7 particle is thereby significantly more tolerant of these types of polypeptide additions than Qbeta and MS2, the other Leviviridae-derived VLPs in common use.
Engineering the PP7 Virus Capsid as a Peptide Display Platform.,Zhao L, Kopylov M, Potter CS, Carragher B, Finn MG ACS Nano. 2019 Mar 26. doi: 10.1021/acsnano.8b09683. PMID:30912918[3]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
See Also
References
- ↑ Tars K, Fridborg K, Bundule M, Liljas L. Structure determination of bacteriophage PP7 from Pseudomonas aeruginosa: from poor data to a good map. Acta Crystallogr D Biol Crystallogr. 2000 Apr;56(Pt 4):398-405. PMID:10739912
- ↑ Lim F, Downey TP, Peabody DS. Translational repression and specific RNA binding by the coat protein of the Pseudomonas phage PP7. J Biol Chem. 2001 Jun 22;276(25):22507-13. PMID:11306589 doi:10.1074/jbc.M102411200
- ↑ Zhao L, Kopylov M, Potter CS, Carragher B, Finn MG. Engineering the PP7 Virus Capsid as a Peptide Display Platform. ACS Nano. 2019 Mar 26. doi: 10.1021/acsnano.8b09683. PMID:30912918 doi:http://dx.doi.org/10.1021/acsnano.8b09683
