Structural highlights
Function
[Q65613_POVBK] Forms an icosahedral capsid with a T=7 symmetry.[PIRNR:PIRNR003376] [VP2_POVBK] Isoform VP2 is a structural protein that resides within the core of the capsid surrounded by 72 VP1 pentamers. Participates in host cell receptor binding together with VP1. Following virus endocytosis and trafficking to the endoplasmic reticulum, VP2 and VP3 form oligomers and integrate into the endoplasmic reticulum membrane. Heterooligomer VP2-VP3 may create a viroporin for transporting the viral genome across the endoplasmic reticulum membrane to the cytoplasm. Nuclear entry of the viral DNA involves the selective exposure and importin recognition of VP2 or Vp3 nuclear localization signal (shared C-terminus). Plays a role in virion assembly within the nucleus in particular through a DNA-binding domain located in the C-terminal region. A N-terminal myristoylation suggests a scaffold function for virion assembly (By similarity). Isoform VP3: structural protein that resides within the core of the capsid surrounded by 72 VP1 pentamers. Following virus endocytosis and trafficking to the endoplasmic reticulum, VP2 and VP3 form oligomers and integrate into the endoplasmic reticulum membrane. Heterooligomer VP2-VP3 may create a viroporin for transporting the viral genome across the endoplasmic reticulum membrane to the cytoplasm. Nuclear entry of the viral DNA involves the selective exposure and importin recognition of VP2 or Vp3 nuclear localization signal (shared C-terminus). Isoform VP3 plays a role in virion assembly within the nucleus. May participate in host cell lysis when associated with VP4 (By similarity). Isoform VP4 is a viroporin inducing perforation of cellular membranes to trigger virus progeny release. Forms pores of 3 nm inner diameter. VP4 is expressed about 24 hours after the late structural proteins and is not incorporated into the mature virion (By similarity).
Publication Abstract from PubMed
BK polyomavirus (BKV) causes polyomavirus-associated nephropathy and hemorrhagic cystitis in immunosuppressed patients. These are diseases for which we currently have limited treatment options, but potential therapies could include pre-transplant vaccination with a multivalent BKV vaccine or therapeutics which inhibit capsid assembly or block attachment and entry into target cells. A useful tool in such efforts would be a high-resolution structure of the infectious BKV virion and how this interacts with its full repertoire of cellular receptors. We present the 3.4-A cryoelectron microscopy structure of native, infectious BKV in complex with the receptor fragment of GT1b ganglioside. We also present structural evidence that BKV can utilize glycosaminoglycans as attachment receptors. This work highlights features that underpin capsid stability and provides a platform for rational design and development of urgently needed pharmacological interventions for BKV-associated diseases.
The Structure of an Infectious Human Polyomavirus and Its Interactions with Cellular Receptors.,Hurdiss DL, Frank M, Snowden JS, Macdonald A, Ranson NA Structure. 2018 Apr 21. pii: S0969-2126(18)30123-0. doi:, 10.1016/j.str.2018.03.019. PMID:29706532[1]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Hurdiss DL, Frank M, Snowden JS, Macdonald A, Ranson NA. The Structure of an Infectious Human Polyomavirus and Its Interactions with Cellular Receptors. Structure. 2018 Apr 21. pii: S0969-2126(18)30123-0. doi:, 10.1016/j.str.2018.03.019. PMID:29706532 doi:http://dx.doi.org/10.1016/j.str.2018.03.019
