{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,29]],"date-time":"2026-06-29T11:36:06Z","timestamp":1782732966619,"version":"3.54.5"},"reference-count":40,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2025,5,19]],"date-time":"2025-05-19T00:00:00Z","timestamp":1747612800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Center of Excellence in Research on Orphan Diseases\u2014Fondation Courtois (CERMO-FC)"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Viruses"],"abstract":"<jats:p>Human T cell leukemia virus type 1 (HTLV 1) is an oncogenic retrovirus responsible for the development of adult T cell leukemia (ATL). The minus strand of HTLV-1 provirus encodes an oncoprotein named HTLV-1 bZIP factor (HBZ), which plays a pivotal role in viral replication and T cell proliferation. Of particular interest is the spliced HBZ isoform (sHBZ), which is predominantly expressed in ATL cells and localizes within the nucleolus, conferring immortalizing properties to T cells. Our previous study has shown that sHBZ colocalizes and associates with Nucleophosmin\/B23, a nucleolar phosphoprotein with multiple functions. In this study, through an optimized nucleolar isolation method, we first confirmed sHBZ\u2019s nucleolar localization via Western blotting in transfected HEK293T cells, chronically HTLV-1-infected T cell lines, and freshly infected HeLa cells. We further demonstrated that the sHBZ\/B23 association predominantly occurs in the nucleolus by co-immunoprecipitation of cell fractions. Our study highlights the nucleolar localization of sHBZ and its possibly essential interaction with this nucleolar-residing protein, leading to cell immortalization.<\/jats:p>","DOI":"10.3390\/v17050727","type":"journal-article","created":{"date-parts":[[2025,5,20]],"date-time":"2025-05-20T06:54:28Z","timestamp":1747724068000},"page":"727","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["HTLV-I Basic Leucine Zipper Factor (sHBZ) Actively Associates with Nucleophosmin (B23) in the Nucleolus"],"prefix":"10.3390","volume":"17","author":[{"given":"Nahid","family":"Moghadam","sequence":"first","affiliation":[{"name":"Department of Biological Sciences, University of Quebec at Montreal (UQAM), 141 President-Kennedy Avenue, Montreal, QC H2X 3X8, Canada"},{"name":"Centre d\u2019Excellence en Recherche sur les Maladies Orphelines-Fondation Courtois, 141 President-Kennedy Avenue, Montr\u00e9al, QC H2X 3X8, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yong","family":"Xiao","sequence":"additional","affiliation":[{"name":"Department of Biological Sciences, University of Quebec at Montreal (UQAM), 141 President-Kennedy Avenue, Montreal, QC H2X 3X8, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Francois","family":"Dragon","sequence":"additional","affiliation":[{"name":"Department of Biological Sciences, University of Quebec at Montreal (UQAM), 141 President-Kennedy Avenue, Montreal, QC H2X 3X8, Canada"},{"name":"Centre d\u2019Excellence en Recherche sur les Maladies Orphelines-Fondation Courtois, 141 President-Kennedy Avenue, Montr\u00e9al, QC H2X 3X8, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7186-9756","authenticated-orcid":false,"given":"Benoit","family":"Barbeau","sequence":"additional","affiliation":[{"name":"Department of Biological Sciences, University of Quebec at Montreal (UQAM), 141 President-Kennedy Avenue, Montreal, QC H2X 3X8, Canada"},{"name":"Centre d\u2019Excellence en Recherche sur les Maladies Orphelines-Fondation Courtois, 141 President-Kennedy Avenue, Montr\u00e9al, QC H2X 3X8, Canada"},{"name":"R\u00e9seau Communaut\u00e9s Rurales et \u00c9loign\u00e9es en Sant\u00e9, 385 Sherbrooke East, Montreal, QC H2X 1E3, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,5,19]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"7415","DOI":"10.1073\/pnas.77.12.7415","article-title":"Detection and Isolation of Type C Retrovirus Particles from Fresh and Cultured Lymphocytes of a Patient with Cutaneous T-Cell Lymphoma","volume":"77","author":"Poiesz","year":"1980","journal-title":"Proc. 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