Distinct stabilization of the human T cell leukemia virus type 1 immature Gag lattice Obr, Martin ; https://orcid.org/0000-0003-1756-6564 Percipalle, Mathias Chernikova, Darya Yang, Huixin Thader, Andreas Pinke, Gergely Porley, Dario J Mansky, Louis M. Dick, Robert A. Schur, Florian KM ; https://orcid.org/0000-0003-4790-8078 ddc:570 Human T cell leukemia virus type 1 (HTLV-1) immature particles differ in morphology from other retroviruses, suggesting a distinct way of assembly. Here we report the results of cryo-electron tomography studies of HTLV-1 virus-like particles assembled in vitro, as well as derived from cells. This work shows that HTLV-1 uses a distinct mechanism of Gag–Gag interactions to form the immature viral lattice. Analysis of high-resolution structural information from immature capsid (CA) tubular arrays reveals that the primary stabilizing component in HTLV-1 is the N-terminal domain of CA. Mutagenesis analysis supports this observation. This distinguishes HTLV-1 from other retroviruses, in which the stabilization is provided primarily by the C-terminal domain of CA. These results provide structural details of the quaternary arrangement of Gag for an immature deltaretrovirus and this helps explain why HTLV-1 particles are morphologically distinct. Springer Nature 2025 info:eu-repo/semantics/article doc-type:article text http://purl.org/coar/resource_type/c_2df8fbb1 https://research-explorer.ista.ac.at/record/17884 https://research-explorer.ista.ac.at/download/17884/19608 Obr M, Percipalle M, Chernikova D, et al. Distinct stabilization of the human T cell leukemia virus type 1 immature Gag lattice. <i>Nature Structural &#38; Molecular Biology</i>. 2025;32:268-276. doi:<a href="https://doi.org/10.1038/s41594-024-01390-8">10.1038/s41594-024-01390-8</a> eng info:eu-repo/semantics/altIdentifier/doi/10.1038/s41594-024-01390-8 info:eu-repo/semantics/altIdentifier/issn/1545-9993 info:eu-repo/semantics/altIdentifier/e-issn/1545-9985 info:eu-repo/semantics/altIdentifier/wos/001306564000001 info:eu-repo/semantics/altIdentifier/pmid/39242978 https://creativecommons.org/licenses/by/4.0/ info:eu-repo/semantics/openAccess