6ilm

Cryo-EM structure of Echovirus 6 complexed with its uncoating receptor FcRn at PH 7.4Cryo-EM structure of Echovirus 6 complexed with its uncoating receptor FcRn at PH 7.4

6ilm, resolution 3.40Å Show:Asymmetric Unit Biological Assembly Structural highlights 6ilm is a 6 chain structure with sequence from Echovirus e6 and Human. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance. Ligands: Gene: FCRN (HUMAN) Experimental data: Check Resources: FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT Disease [B2MG_HUMAN] Defects in B2M are the cause of hypercatabolic hypoproteinemia (HYCATHYP) [MIM:241600]. Affected individuals show marked reduction in serum concentrations of immunoglobulin and albumin, probably due to rapid degradation. Note=Beta-2-microglobulin may adopt the fibrillar configuration of amyloid in certain pathologic states. The capacity to assemble into amyloid fibrils is concentration dependent. Persistently high beta(2)-microglobulin serum levels lead to amyloidosis in patients on long-term hemodialysis. Function [B2MG_HUMAN] Component of the class I major histocompatibility complex (MHC). Involved in the presentation of peptide antigens to the immune system. [FCGRN_HUMAN] Binds to the Fc region of monomeric immunoglobulins gamma. Mediates the uptake of IgG from milk. Possible role in transfer of immunoglobulin G from mother to fetus. Publication Abstract from PubMed Enterovirus B (EV-B), a major proportion of the genus Enterovirus in the family Picornaviridae, is the causative agent of severe human infectious diseases. Although cellular receptors for coxsackievirus B in EV-B have been identified, receptors mediating virus entry, especially the uncoating process of echovirus and other EV-B remain obscure. Here, we found that human neonatal Fc receptor (FcRn) is the uncoating receptor for major EV-B. FcRn binds to the virus particles in the "canyon" through its FCGRT subunit. By obtaining multiple cryo-electron microscopy structures at different stages of virus entry at atomic or near-atomic resolution, we deciphered the underlying mechanisms of enterovirus attachment and uncoating. These structures revealed that different from the attachment receptor CD55, binding of FcRn to the virions induces efficient release of "pocket factor" under acidic conditions and initiates the conformational changes in viral particle, providing a structural basis for understanding the mechanisms of enterovirus entry. Human Neonatal Fc Receptor Is the Cellular Uncoating Receptor for Enterovirus B.,Zhao X, Zhang G, Liu S, Chen X, Peng R, Dai L, Qu X, Li S, Song H, Gao Z, Yuan P, Liu Z, Li C, Shang Z, Li Y, Zhang M, Qi J, Wang H, Du N, Wu Y, Bi Y, Gao S, Shi Y, Yan J, Zhang Y, Xie Z, Wei W, Gao GF Cell. 2019 May 30;177(6):1553-1565.e16. doi: 10.1016/j.cell.2019.04.035. Epub, 2019 May 16. PMID:31104841 From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.