{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,29]],"date-time":"2026-09-29T08:22:11Z","timestamp":1790670131171,"version":"4.1.0"},"reference-count":45,"publisher":"MDPI AG","issue":"16","license":[{"start":{"date-parts":[[2023,8,10]],"date-time":"2023-08-10T00:00:00Z","timestamp":1691625600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"University of Lille"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>The Protein Phosphatase type 1 catalytic subunit (PP1c) (PF3D7_1414400) operates in combination with various regulatory proteins to specifically direct and control its phosphatase activity. However, there is little information about this phosphatase and its regulators in the human malaria parasite, Plasmodium falciparum. To address this knowledge gap, we conducted a comprehensive investigation into the structural and functional characteristics of a conserved Plasmodium-specific regulator called Gametocyte EXported Protein 15, GEXP15 (PF3D7_1031600). Through in silico analysis, we identified three significant regions of interest in GEXP15: an N-terminal region housing a PP1-interacting RVxF motif, a conserved domain whose function is unknown, and a GYF-like domain that potentially facilitates specific protein\u2013protein interactions. To further elucidate the role of GEXP15, we conducted in vitro interaction studies that demonstrated a direct interaction between GEXP15 and PP1 via the RVxF-binding motif. This interaction was found to enhance the phosphatase activity of PP1. Additionally, utilizing a transgenic GEXP15-tagged line and live microscopy, we observed high expression of GEXP15 in late asexual stages of the parasite, with localization predominantly in the nucleus. Immunoprecipitation assays followed by mass spectrometry analyses revealed the interaction of GEXP15 with ribosomal- and RNA-binding proteins. Furthermore, through pull-down analyses of recombinant functional domains of His-tagged GEXP15, we confirmed its binding to the ribosomal complex via the GYF domain. Collectively, our study sheds light on the PfGEXP15\u2013PP1\u2013ribosome interaction, which plays a crucial role in protein translation. These findings suggest that PfGEXP15 could serve as a potential target for the development of malaria drugs.<\/jats:p>","DOI":"10.3390\/ijms241612647","type":"journal-article","created":{"date-parts":[[2023,8,10]],"date-time":"2023-08-10T10:11:22Z","timestamp":1691662282000},"page":"12647","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["Characterization of GEXP15 as a Potential Regulator of Protein Phosphatase 1 in Plasmodium falciparum"],"prefix":"10.3390","volume":"24","author":[{"given":"Hala","family":"Mansour","sequence":"first","affiliation":[{"name":"Univ. Lille, CNRS, Inserm, CHU Lille, Institut Pasteur de Lille, U1019-UMR 9017-CIIL-Center for Infection and Immunity of Lille, 59000 Lille, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8660-730X","authenticated-orcid":false,"given":"Alejandro","family":"Cabezas-Cruz","sequence":"additional","affiliation":[{"name":"ANSES, INRAE, Ecole Nationale V\u00e9t\u00e9rinaire d\u2019Alfort, UMR BIPAR, Laboratoire de Sant\u00e9 Animale, 94700 Maisons-Alfort, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"V\u00e9ronique","family":"Peucelle","sequence":"additional","affiliation":[{"name":"Univ. Lille, CNRS, Inserm, CHU Lille, Institut Pasteur de Lille, U1019-UMR 9017-CIIL-Center for Infection and Immunity of Lille, 59000 Lille, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Amaury","family":"Farce","sequence":"additional","affiliation":[{"name":"Univ. Lille, Inserm, CHU Lille, U1286\u2013Infinite\u2013Institute for Translational Research in Inflammation, 59000 Lille, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sophie","family":"Salom\u00e9-Desnoulez","sequence":"additional","affiliation":[{"name":"Univ. Lille, CNRS, Inserm, CHU Lille, Institut Pasteur de Lille, US 41\u2013UAR 2014\u2013PLBS, 59000 Lille, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0004-1813-7520","authenticated-orcid":false,"given":"Ines","family":"Metatla","sequence":"additional","affiliation":[{"name":"Proteomics Platform Necker, Universit\u00e9 Paris Cit\u00e9\u2013Structure F\u00e9d\u00e9rative de Recherche Necker, INSERM US24\/CNRS UAR3633, 75015 Paris, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4832-6793","authenticated-orcid":false,"given":"Ida Chiara","family":"Guerrera","sequence":"additional","affiliation":[{"name":"Proteomics Platform Necker, Universit\u00e9 Paris Cit\u00e9\u2013Structure F\u00e9d\u00e9rative de Recherche Necker, INSERM US24\/CNRS UAR3633, 75015 Paris, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Thomas","family":"Hollin","sequence":"additional","affiliation":[{"name":"Univ. Lille, CNRS, Inserm, CHU Lille, Institut Pasteur de Lille, U1019-UMR 9017-CIIL-Center for Infection and Immunity of Lille, 59000 Lille, France"},{"name":"Department of Molecular, Cell and Systems Biology, University of California Riverside, Riverside, CA 92521, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jamal","family":"Khalife","sequence":"additional","affiliation":[{"name":"Univ. Lille, CNRS, Inserm, CHU Lille, Institut Pasteur de Lille, U1019-UMR 9017-CIIL-Center for Infection and Immunity of Lille, 59000 Lille, France"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,8,10]]},"reference":[{"key":"ref_1","unstructured":"(2023, May 03). World Malaria Report 2022. 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