4zxs
From Proteopedia
HSV-1 nuclear egress complex
Structural highlights
FunctionNEC2_HHV11 Plays an essential role in virion nuclear egress, the first step of virion release from infected cell. Within the host nucleus, NEC1 interacts with the newly formed capsid through the vertexes and directs it to the inner nuclear membrane by associating with NEC2. Induces the budding of the capsid at the inner nuclear membrane as well as its envelopment into the perinuclear space. There, the NEC1/NEC2 complex promotes the fusion of the enveloped capsid with the outer nuclear membrane and the subsequent release of the viral capsid into the cytoplasm where it will reach the secondary budding sites in the host Golgi or trans-Golgi network.[HAMAP-Rule:MF_04024][1] [2] [3] Publication Abstract from PubMedDuring nuclear egress, herpesvirus capsids bud at the inner nuclear membrane forming perinuclear viral particles that subsequently fuse with the outer nuclear membrane, releasing capsids into the cytoplasm. This unusual budding process is mediated by the nuclear egress complex (NEC) composed of two conserved viral proteins, UL31 and UL34. Earlier, we discovered that the herpesvirus nuclear egress complex (NEC) could bud synthetic membranes in vitro without the help of other proteins by forming a coat-like hexagonal scaffold inside the budding membrane. To understand the structural basis of NEC-mediated membrane budding, we determined the crystal structures of the NEC from two herpesviruses. The hexagonal lattice observed in the NEC crystals recapitulates the honeycomb coats within the budded vesicles. Perturbation of the oligomeric interfaces through mutagenesis blocks budding in vitro confirming that NEC oligomerization into a honeycomb lattice drives budding. The structure represents the first atomic-level view of an oligomeric array formed by a membrane-deforming protein, making possible the dissection of its unique budding mechanism and the design of inhibitors to block it. Structural basis of membrane budding by the nuclear egress complex of herpesviruses.,Bigalke JM, Heldwein EE EMBO J. 2015 Dec 2;34(23):2921-36. doi: 10.15252/embj.201592359. Epub 2015 Oct, 28. PMID:26511020[4] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. References
|