5cez
From Proteopedia
Crystal Structure of the BG505 SOSIP gp140 HIV-1 Env trimer in Complex with an early putative precursor of the PGT121 family at 3.0 Angstrom
Structural highlights
FunctionQ2N0S6_9HIV1 The envelope glyprotein gp160 precursor down-modulates cell surface CD4 antigen by interacting with it in the endoplasmic reticulum and blocking its transport to the cell surface (By similarity).[RuleBase:RU004292][SAAS:SAAS000328_004_020447] The gp120-gp41 heterodimer allows rapid transcytosis of the virus through CD4 negative cells such as simple epithelial monolayers of the intestinal, rectal and endocervical epithelial barriers. Both gp120 and gp41 specifically recognize glycosphingolipids galactosyl-ceramide (GalCer) or 3' sulfo-galactosyl-ceramide (GalS) present in the lipid rafts structures of epithelial cells. Binding to these alternative receptors allows the rapid transcytosis of the virus through the epithelial cells. This transcytotic vesicle-mediated transport of virions from the apical side to the basolateral side of the epithelial cells does not involve infection of the cells themselves (By similarity).[SAAS:SAAS000328_004_240990] Publication Abstract from PubMedThe high-mannose patch on the HIV-1 envelope (Env) glycoprotein is the epicenter for binding of the potent broadly neutralizing PGT121 family of antibodies, but strategies for generating such antibodies by vaccination have not been defined. We generated structures of inferred antibody intermediates by X-ray crystallography and electron microscopy to elucidate the molecular events that occurred during evolution of this family. Binding analyses revealed that affinity maturation was primarily focused on avoiding, accommodating, or binding the N137 glycan. The overall antibody approach angle to Env was defined very early in the maturation process, yet some variation evolved in the PGT121 family branches that led to differences in glycan specificities in their respective epitopes. Furthermore, we determined a crystal structure of the recombinant BG505 SOSIP.664 HIV-1 trimer with a PGT121 family member at 3.0 A that, in concert with these antibody intermediate structures, provides insights to advance design of HIV vaccine candidates. Affinity Maturation of a Potent Family of HIV Antibodies Is Primarily Focused on Accommodating or Avoiding Glycans.,Garces F, Lee JH, de Val N, Torrents de la Pena A, Kong L, Puchades C, Hua Y, Stanfield RL, Burton DR, Moore JP, Sanders RW, Ward AB, Wilson IA Immunity. 2015 Dec 15;43(6):1053-63. doi: 10.1016/j.immuni.2015.11.007. PMID:26682982[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. References
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