11BD

human nucleosome assembly protein 1 (human Nap1)

Summary for 11BD

• Entry DOI: 10.2210/pdb11bd/pdb
• Descriptor: Nucleosome assembly protein 1-like 1 (1 entity in total)
• Functional Keywords: histone, h2a-h2b, nucleosome assembly protein 1, nucleosome assembly protein like 1, chaperone
• Biological source: Homo sapiens (human)
• Total number of polymer chains: 2
• Total formula weight: 68719.35

Authors

Eren, E. (deposition date: 2026-02-15, release date: 2026-05-13, Last modification date: 2026-05-20)

Primary citation

Eren, E.,Watts, N.R.,Winkler, D.C.,Wingfield, P.T.
Structural Basis for HIV-1 Rev Recognition by the Histone Chaperone Human Nap1.
J.Biol.Chem., :113120-113120, 2026

PubMed Abstract: Human Nap1 (hNap1) is a histone chaperone involved in chromatin dynamics and has been shown to interact with the HIV-1 regulatory protein Rev, which is essential for nuclear export of viral RNA. Despite the functional significance of this interaction, its structural basis has remained elusive. Here, we present the X-ray crystal structure of hNap1 and the cryo-electron microscopy structure of the core domain of hNap1-Rev complex. The structure reveals that hNap1 binds Rev dimers via its acidic concave surface, engaging the Rev arginine-rich motif and oligomerization domain, and stabilizes Rev as a dimer-of-dimers tetramer. This interaction prevents higher-order Rev aggregation and enhances Rev's cooperative binding to the Rev Response Element. Surface plasmon resonance measurements confirm the formation of a stable complex with an apparent low-micromolar affinity between hNap1 and Rev, supporting a chaperone-like, reversible association. Our findings provide molecular insight into how hNap1 modulates Rev assembly and function, suggesting a model in which hNap1 primes Rev for productive engagement with viral RNA, thereby facilitating HIV-1 replication.

PubMed: 42103228
DOI: 10.1016/j.jbc.2026.113120

Experimental method

X-RAY DIFFRACTION (3.2 Å)