{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,20]],"date-time":"2026-07-20T14:14:34Z","timestamp":1784556874439,"version":"3.55.0"},"reference-count":31,"publisher":"Wiley","issue":"5","license":[{"start":{"date-parts":[[2026,5,7]],"date-time":"2026-05-07T00:00:00Z","timestamp":1778112000000},"content-version":"vor","delay-in-days":6,"URL":"http:\/\/creativecommons.org\/licenses\/by-nc-nd\/4.0\/"},{"start":{"date-parts":[[2026,5,1]],"date-time":"2026-05-01T00:00:00Z","timestamp":1777593600000},"content-version":"tdm","delay-in-days":0,"URL":"http:\/\/doi.wiley.com\/10.1002\/tdm_license_1.1"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Biotechnology Journal"],"published-print":{"date-parts":[[2026,5]]},"abstract":"<jats:title>ABSTRACT<\/jats:title>\n                  <jats:p>\n                    <jats:italic>Toxoplasma gondii<\/jats:italic>\n                    is an intracellular eukaryotic parasite in the phylum Apicomplexa. Reversible, conditional control of gene transcription was achieved previously in this organism using a tet\u2010off system that was controlled by tetracycline. Although revolutionary for the field at the time, that system in\n                    <jats:italic>Toxoplasma<\/jats:italic>\n                    yielded modest signal\u2010to\u2010noise ratios (SNR) and proved to be leaky in the \u201coff\u201d state (i.e., it suffered from high background expression). Here we report the development of a new reversible and robust Conditional Transcription Factor (CTF) that is controlled by rapamycin. Although we originally intended to design a dimerizable drug\u2010on transcription control system, the CTF unexpectedly functions in a drug\u2010off fashion. In stably\u2010transfected tachyzoites, CTF regulates a fluorescent reporter gene in\n                    <jats:italic>Toxoplasma<\/jats:italic>\n                    to achieve almost no background expression in the presence of rapamycin (i.e. near\u2010zero leakiness), while in the absence of rapamycin 84% of tachyzoites express EYFP in comparison with 87% of constitutively\u2010expressed positive controls, with 59% mean fluorescence intensity relative to positive controls. Conditional regulation of the median fluorescence intensity of the reporter gene reached an impressive SNR averaging 1489, approximating an \u201con\/off\u201d switch. The modular design of the CTF is expected to facilitate application to varied genes, incremental modifications, and adaptation for use in other apicomplexan organisms.\n                  <\/jats:p>","DOI":"10.1002\/biot.70240","type":"journal-article","created":{"date-parts":[[2026,5,7]],"date-time":"2026-05-07T10:56:21Z","timestamp":1778151381000},"source":"Crossref","is-referenced-by-count":0,"title":["A New Conditional Transcription Factor for Use in\n                    <i>Toxoplasma Gondii<\/i>"],"prefix":"10.1002","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-7950-955X","authenticated-orcid":false,"given":"Mohammad Farouq","family":"Sharifpour","sequence":"first","affiliation":[{"name":"Australian Institute of Tropical Health and Medicine James Cook University  Townsville Queensland Australia"},{"name":"School of Animal and Veterinary Sciences Roseworthy Campus Adelaide University  Roseworthy South Australia Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shadi","family":"Khadiv","sequence":"additional","affiliation":[{"name":"School of Veterinary Sciences College of Science and Engineering James Cook University  Townsville Queensland Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alessandro D.","family":"Uboldi","sequence":"additional","affiliation":[{"name":"The Walter and Eliza Hall Institute of Medical Research  Parkville Victoria Australia"},{"name":"Department of Medical Biology The University of Melbourne  Melbourne Victoria Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Amalie A.","family":"Jayawickrama","sequence":"additional","affiliation":[{"name":"The Walter and Eliza Hall Institute of Medical Research  Parkville Victoria Australia"},{"name":"Department of Medical Biology The University of Melbourne  Melbourne Victoria Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sarah","family":"Manning","sequence":"additional","affiliation":[{"name":"South Australian Health and Medical Research Institute  Adelaide South Australia Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jonathan","family":"Whittall","sequence":"additional","affiliation":[{"name":"School of Biological Sciences Adelaide University  Adelaide South Australia Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6245-0099","authenticated-orcid":false,"given":"Cynthia D. K.","family":"Bottema","sequence":"additional","affiliation":[{"name":"School of Animal and Veterinary Sciences Roseworthy Campus Adelaide University  Roseworthy South Australia Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"John T.","family":"Ellis","sequence":"additional","affiliation":[{"name":"School of Life Sciences University of Technology \u2013 Sydney  Sydney New South Wales Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Daniel K.","family":"Howe","sequence":"additional","affiliation":[{"name":"Department of Veterinary Science Maxwell H. Gluck Equine Research Center University of Kentucky  Lexington Kentucky USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Danny W.","family":"Wilson","sequence":"additional","affiliation":[{"name":"Research Centre For Infectious Diseases School of Biological Sciences Adelaide University  Adelaide South Australia Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Farhid","family":"Hemmatzadeh","sequence":"additional","affiliation":[{"name":"School of Animal and Veterinary Sciences Roseworthy Campus Adelaide University  Roseworthy South Australia Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Christopher J.","family":"Tonkin","sequence":"additional","affiliation":[{"name":"The Walter and Eliza Hall Institute of Medical Research  Parkville Victoria Australia"},{"name":"Department of Medical Biology The University of Melbourne  Melbourne Victoria Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Milton M.","family":"McAllister","sequence":"additional","affiliation":[{"name":"School of Animal and Veterinary Sciences Roseworthy Campus Adelaide University  Roseworthy South Australia Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"311","published-online":{"date-parts":[[2026,5,7]]},"reference":[{"key":"e_1_2_11_2_1","doi-asserted-by":"publisher","DOI":"10.1016\/s0020\u20107519(00)00124\u20107"},{"key":"e_1_2_11_3_1","doi-asserted-by":"publisher","DOI":"10.1098\/rspb.2006.3641"},{"key":"e_1_2_11_4_1","doi-asserted-by":"publisher","DOI":"10.1891\/0730\u20100832.20.4.23"},{"key":"e_1_2_11_5_1","doi-asserted-by":"publisher","DOI":"10.4269\/ajtmh.2010.09\u20100664"},{"key":"e_1_2_11_6_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.schres.2013.07.028"},{"key":"e_1_2_11_7_1","doi-asserted-by":"publisher","DOI":"10.1017\/S0033291719000813"},{"key":"e_1_2_11_8_1","doi-asserted-by":"publisher","DOI":"10.1093\/schbul\/sbl050"},{"key":"e_1_2_11_9_1","doi-asserted-by":"publisher","DOI":"10.1002\/ijc.33443"},{"key":"e_1_2_11_10_1","doi-asserted-by":"publisher","DOI":"10.1017\/S0950268818002194"},{"key":"e_1_2_11_11_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.ijpara.2003.12.009"},{"key":"e_1_2_11_12_1","doi-asserted-by":"publisher","DOI":"10.1016\/s1367\u20105931(02)00377\u20100"},{"key":"e_1_2_11_13_1","doi-asserted-by":"publisher","DOI":"10.1002\/1873\u20103468.12993"},{"key":"e_1_2_11_14_1","doi-asserted-by":"publisher","DOI":"10.2144\/05392ST01"},{"key":"e_1_2_11_15_1","doi-asserted-by":"publisher","DOI":"10.1126\/science.1074553"},{"key":"e_1_2_11_16_1","doi-asserted-by":"publisher","DOI":"10.1101\/pdb.prot070136"},{"key":"e_1_2_11_17_1","doi-asserted-by":"publisher","DOI":"10.1007\/978-3-540-35109-2_3"},{"key":"e_1_2_11_18_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.molbiopara.2021.111384"},{"key":"e_1_2_11_19_1","doi-asserted-by":"publisher","DOI":"10.1111\/mmi.14821"},{"key":"e_1_2_11_20_1","doi-asserted-by":"publisher","DOI":"10.1128\/AAC.47.1.309\u2010316.2003"},{"key":"e_1_2_11_21_1","doi-asserted-by":"publisher","DOI":"10.1016\/0022\u20102836(89)90007\u20107"},{"key":"e_1_2_11_22_1","doi-asserted-by":"publisher","DOI":"10.1038\/335563a0"},{"key":"e_1_2_11_23_1","doi-asserted-by":"publisher","DOI":"10.1126\/science.3080805"},{"key":"e_1_2_11_24_1","doi-asserted-by":"publisher","DOI":"10.1016\/0092\u20108674(84)90457\u20104"},{"key":"e_1_2_11_25_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.chom.2012.10.016"},{"key":"e_1_2_11_26_1","doi-asserted-by":"publisher","DOI":"10.1016\/0092\u20108674(85)90336\u20108"},{"key":"e_1_2_11_27_1","doi-asserted-by":"publisher","DOI":"10.1016\/s0092\u20108674(88)80010\u20102"},{"key":"e_1_2_11_28_1","doi-asserted-by":"publisher","DOI":"10.1038\/s41477\u2010021\u201000932\u2010y"},{"key":"e_1_2_11_29_1","doi-asserted-by":"publisher","DOI":"10.1073\/pnas.0914803107"},{"key":"e_1_2_11_30_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.ijpara.2006.01.005"},{"key":"e_1_2_11_31_1","doi-asserted-by":"publisher","DOI":"10.1093\/nar\/29.22.e115"},{"key":"e_1_2_11_32_1","doi-asserted-by":"publisher","DOI":"10.1371\/journal.pgen.1008865"}],"container-title":["Biotechnology 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