{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,18]],"date-time":"2026-01-18T11:09:49Z","timestamp":1768734589490,"version":"3.49.0"},"reference-count":27,"publisher":"Public Library of Science (PLoS)","issue":"4","license":[{"start":{"date-parts":[[2021,4,15]],"date-time":"2021-04-15T00:00:00Z","timestamp":1618444800000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100011512","name":"National Research Foundation","doi-asserted-by":"publisher","award":["SFH14061869970"],"award-info":[{"award-number":["SFH14061869970"]}],"id":[{"id":"10.13039\/100011512","id-type":"DOI","asserted-by":"publisher"}]},{"name":"The University of Kwa-Zulu Natal College of Health Sciences"}],"content-domain":{"domain":["www.plosone.org"],"crossmark-restriction":false},"short-container-title":["PLoS ONE"],"abstract":"<jats:p><jats:italic>Chlamydia trachomatis<\/jats:italic> infects squamous and columnar epithelia at the mucosal surface. Research on gene expression patterns of <jats:italic>C<\/jats:italic>. <jats:italic>trachomatis<\/jats:italic> has predominantly focused on non-native host cells, with limited data on growth kinetics and gene expression of chlamydia in keratinocytes. Here, we investigated whether early, mid, and late chlamydial genes observed in HeLa cell line studies were co-ordinately regulated at the transcriptional level even in the keratinized cell line model and whether the expression was stage-specific during the developmental cycle. HaCaT cell lines were infected with chlamydia clinical isolates (US151and serovar E) and reference strain (L2 434). Expression of <jats:italic>groEL-1<\/jats:italic>, <jats:italic>incB<\/jats:italic>, <jats:italic>pyk-F<\/jats:italic>, <jats:italic>tal<\/jats:italic>, <jats:italic>hctA<\/jats:italic>, and <jats:italic>omcB<\/jats:italic> genes was conducted with comparative real-time PCR and transcriptional events during the chlamydial developmental cycle using transmission electron microscopy. The relative expression level of each gene and fold difference were calculated using the 2<jats:sup>-\u0394\u0394CT<\/jats:sup> method. The expression of <jats:italic>groEL-1<\/jats:italic> and <jats:italic>pyk-F<\/jats:italic> genes was highest at 2 hours post-infection (hpi) in the L2 434 and serovar E. The expression of <jats:italic>incB<\/jats:italic> gene increased at 2 hpi in L2 434 and serovar E but peaked at 12 hpi in serovar E. L2 434 and US151 had similar <jats:italic>tal<\/jats:italic> expression profiles. Increased expression of <jats:italic>hctA<\/jats:italic> and <jats:italic>omcB<\/jats:italic> genes were found at 2 and 36 hpi in L2 434. Both clinical isolates and reference strains presented the normal chlamydial replication cycle comprising elementary bodies and reticulate bodies within 36 hpi. We show different gene expression patterns between clinical isolates and reference strain during <jats:italic>in vitro<\/jats:italic> infection of keratinocytes, with reference strain-inducing consistent expression of genes. These findings confirm that keratinocytes are appropriate cell lines to interrogate cell differentiation, growth kinetics, and gene expression of <jats:italic>C<\/jats:italic>. <jats:italic>trachomatis<\/jats:italic> infection. Furthermore, more studies with different clinical isolates and genes are needed to better understand the Chlamydial pathogenesis in keratinocytes.<\/jats:p>","DOI":"10.1371\/journal.pone.0249358","type":"journal-article","created":{"date-parts":[[2021,4,15]],"date-time":"2021-04-15T23:59:27Z","timestamp":1618531167000},"page":"e0249358","update-policy":"https:\/\/doi.org\/10.1371\/journal.pone.corrections_policy","source":"Crossref","is-referenced-by-count":2,"title":["Differential expression of groEL-1, incB, pyk-F, tal, hctA and omcB genes during Chlamydia trachomatis developmental cycle"],"prefix":"10.1371","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-1850-7371","authenticated-orcid":true,"given":"Gugulethu F.","family":"Mzobe","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Sinaye","family":"Ngcapu","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Bronwyn C.","family":"Joubert","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7521-8248","authenticated-orcid":true,"given":"Willem A.","family":"Sturm","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"340","published-online":{"date-parts":[[2021,4,15]]},"reference":[{"key":"pone.0249358.ref001","unstructured":"WHO, Report on global sexually transmitted infection surveillance, 2018. 2018, World Health Organization: Geneva, Switzerland."},{"key":"pone.0249358.ref002","doi-asserted-by":"crossref","first-page":"438","DOI":"10.3389\/fcimb.2017.00438","article-title":"Characterization of the Growth of Chlamydia trachomatis in In Vitro-Generated Stratified Epithelium.","volume":"7","author":"A.T. 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Wickstrum","year":"2013","journal-title":"PloS one"}],"container-title":["PLOS ONE"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/dx.plos.org\/10.1371\/journal.pone.0249358","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2021,4,15]],"date-time":"2021-04-15T23:59:56Z","timestamp":1618531196000},"score":1,"resource":{"primary":{"URL":"https:\/\/dx.plos.org\/10.1371\/journal.pone.0249358"}},"subtitle":[],"editor":[{"given":"Michael F.","family":"Minnick","sequence":"first","affiliation":[],"role":[{"role":"editor","vocabulary":"crossref"}]}],"short-title":[],"issued":{"date-parts":[[2021,4,15]]},"references-count":27,"journal-issue":{"issue":"4","published-online":{"date-parts":[[2021,4,15]]}},"URL":"https:\/\/doi.org\/10.1371\/journal.pone.0249358","relation":{},"ISSN":["1932-6203"],"issn-type":[{"value":"1932-6203","type":"electronic"}],"subject":[],"published":{"date-parts":[[2021,4,15]]}}}