9mks

From Proteopedia

MVV CA Hexamer Assembled via Liposome Templating

Structural highlights

9mks is a 1 chain structure with sequence from Visna-maedi virus. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
Method:	Electron Microscopy, Resolution 3.13Å
Resources:	FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT

Function

GAG_VILV Mediates, with Gag-Pol polyprotein, the essential events in virion assembly, including binding the plasma membrane, making the protein-protein interactions necessary to create spherical particles, recruiting the viral Env proteins, and packaging the genomic RNA via direct interactions with the RNA packaging sequence.[UniProtKB:P04585] Targets the polyprotein to the plasma membrane.[UniProtKB:P12497] Forms the core that encapsulates the genomic RNA-nucleocapsid complex in the virion.[UniProtKB:P04585] Encapsulates and protects viral dimeric unspliced genomic RNA (gRNA). Binds these RNAs through its zinc fingers. Acts as a nucleic acid chaperone which is involved in rearrangement of nucleic acid secondary structure during gRNA retrotranscription. Also facilitates template switch leading to recombination.[UniProtKB:P04585]

Publication Abstract from PubMed

Lentiviruses require a mature capsid to package and traffic their viral genome for successful infection and propagation. Although the HIV-1 capsid structure has been extensively studied, structural information is lacking for other lentiviral capsids, limiting our understanding. Using cryo-electron microscopy (cryo-EM) and a liposome-templating system, we assembled capsid-like particles (CLPs) and resolved capsid protein (CA) pentamer and hexamer lattice structures from the two major phylogenetic groups of small ruminant lentiviruses (SRLVs). These structures exhibit an overall lattice organization like HIV-1 but differ in key characteristics, notably the absence of inositol hexakisphosphate (IP6) in the SRLV CA lattice horizontal line a critical factor for HIV-1 capsid assembly and function. Additionally, SRLV CA pentamers show a unique N-terminal domain orientation, providing insights into SRLV capsid assembly mechanisms. These observations, together with our molecular dynamics (MD) simulation, results suggest a possible mechanism for importing deoxynucleotide triphosphate (dNTP) molecules into SRLV capsids. Furthermore, key regions of host factor interaction, such as the CypA binding motifs, have diverged in the SRLV CA assemblies. Our results contribute to understanding the SRLV lentiviral capsids which may facilitate structure-based inhibitor design strategies.

Exploring the Structural Divergence of HIV and SRLV Lentiviral Capsids.,Arizaga F Jr, Freniere C, Rey JS, Cook M, Wu C, Perilla JR, Xiong Y J Am Chem Soc. 2025 Sep 10;147(36):32883-32895. doi: 10.1021/jacs.5c09436. Epub , 2025 Aug 29. PMID:40878534^[1]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

References

↑ Arizaga F Jr, Freniere C, Rey JS, Cook M, Wu C, Perilla JR, Xiong Y. Exploring the Structural Divergence of HIV and SRLV Lentiviral Capsids. J Am Chem Soc. 2025 Sep 10;147(36):32883-32895. PMID:40878534 doi:10.1021/jacs.5c09436