{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"institution":[{"name":"bioRxiv"}],"indexed":{"date-parts":[[2026,3,29]],"date-time":"2026-03-29T17:47:39Z","timestamp":1774806459070,"version":"3.50.1"},"posted":{"date-parts":[[2026,3,12]]},"group-title":"Microbiology","reference-count":62,"publisher":"openRxiv","license":[{"start":{"date-parts":[[2026,3,12]],"date-time":"2026-03-12T00:00:00Z","timestamp":1773273600000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by-nd\/4.0\/"}],"funder":[{"name":"NIH","award":["AI129529"],"award-info":[{"award-number":["AI129529"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"accepted":{"date-parts":[[2026,3,12]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                <jats:p>\n                  As a master of host-cell reprogramming,\n                  <jats:italic>Toxoplasma gondii<\/jats:italic>\n                  (\n                  <jats:italic>T. gondii<\/jats:italic>\n                  ) tachyzoites manipulate diverse signaling networks to establish a niche permissive for long-term infection. While the parasite\u2019s subversion of canonical NF-\u03baB signaling (p65\/p50) is well established, how infection impacts the non-canonical NF-\u03baB pathway has been largely unexplored. Here, we report that\n                  <jats:italic>T. gondii<\/jats:italic>\n                  infection induces robust nuclear accumulation of the non-canonical NF-\u03baB subunits RelB and p52 in both human and murine cells. This activation follows a gradual kinetic profile and is conserved across both Type I and Type II parasite genetic backgrounds.\n                <\/jats:p>\n                <jats:p>\n                  We demonstrate that this reprogramming is strictly dependent on the MYR1-dependent export of dense granule effectors. Mechanistically,\n                  <jats:italic>T. gondii<\/jats:italic>\n                  infection drives the depletion of the negative regulator TRAF3, leading to the stabilization of NF-\u03baB-inducing kinase (NIK), phosphorylation of p100, and its subsequent processing into p52. Utilizing a panel of combinatorial knockout parasites, we reveal that no single effector is responsible for this phenotype. Instead, a suite of eight MYR1-dependent effectors, IST, NSM, HCE1\/TEEGR, GRA16, GRA18, GRA24, GRA28, and GRA84, functions through a collaborative, additive network to trigger the non-canonical response. These findings highlight a distributed regulatory strategy used by the parasite to overcome host transcriptional robustness and shape host signaling.\n                <\/jats:p>\n                <jats:sec>\n                  <jats:title>Importance<\/jats:title>\n                  <jats:p>\n                    <jats:italic>Toxoplasma gondii<\/jats:italic>\n                    infects nearly one-third of the global population and establishes infection by extensively rewiring host immune signaling. While decades of work have focused on how the parasite modulates canonical NF-\u03baB activity, whether it also engages the alternative, non-canonical arm of this pathway has remained unclear. Here, we show that\n                    <jats:italic>T. gondii<\/jats:italic>\n                    tachyzoites activate non-canonical NF-\u03baB signaling, driving nuclear accumulation of RelB\/p52 through MYR1-dependent effector export. Unexpectedly, no single effector is responsible. Instead, eight secreted proteins act cooperatively to enable NIK stabilization and engage the alternative NF-\u03baB cascade, revealing a networked mode of immune control. This discovery highlights a regulatory logic evolved by the parasite to overcome host transcriptional robustness. Together, these findings identify non-canonical NF-\u03baB activation as a new axis of host-parasite interaction and expand our understanding of how\n                    <jats:italic>T. gondii<\/jats:italic>\n                    reprograms central immune signaling circuits through multi-effector networks.\n                  <\/jats:p>\n                <\/jats:sec>","DOI":"10.64898\/2026.03.12.711255","type":"posted-content","created":{"date-parts":[[2026,3,13]],"date-time":"2026-03-13T04:30:14Z","timestamp":1773376214000},"source":"Crossref","is-referenced-by-count":0,"title":["A Suite of Eight\n                  <i>Toxoplasma gondii<\/i>\n                  Effectors Cooperates to Activate the Non-canonical NF-\u03baB Pathway"],"prefix":"10.64898","author":[{"given":"Kenna","family":"Berg","sequence":"first","affiliation":[{"name":"Department of Infectious Diseases, University of Georgia, Athens, GA, USA"},{"name":"Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, GA, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2973-736X","authenticated-orcid":false,"given":"Michael","family":"Panas","sequence":"additional","affiliation":[{"name":"Department of Microbiology and Immunology, Stanford University School of Medicine, 299 Campus Drive, Stanford, CA 94305, United States"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0640-0502","authenticated-orcid":false,"given":"Samarchith P","family":"Kurup","sequence":"additional","affiliation":[{"name":"Department of Cellular Biology, University of Georgia, Athens, GA, USA"},{"name":"Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, GA, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9719-745X","authenticated-orcid":false,"given":"John C","family":"Boothroyd","sequence":"additional","affiliation":[{"name":"Department of Microbiology and Immunology, Stanford University School of Medicine, 299 Campus Drive, Stanford, CA 94305, United States"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9672-1360","authenticated-orcid":false,"given":"Alex","family":"Rosenberg","sequence":"additional","affiliation":[{"name":"Department of Infectious Diseases, University of Georgia, Athens, GA, USA"},{"name":"Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, GA, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"54368","reference":[{"key":"2026032910415794000_2026.03.12.711255v1.1","doi-asserted-by":"crossref","first-page":"112","DOI":"10.1186\/1756-3305-3-112","article-title":"Dubey, J.P. 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