{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,6]],"date-time":"2026-01-06T15:29:47Z","timestamp":1767713387220,"version":"3.41.2"},"reference-count":25,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2021,6,25]],"date-time":"2021-06-25T00:00:00Z","timestamp":1624579200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Vet. Sci."],"abstract":"<jats:p>The transcriptional regulator MucR is related to normal growth, stress responses and <jats:italic>Brucella<\/jats:italic> virulence, and affects the expression of various virulence-related genes in smooth-type <jats:italic>Brucella<\/jats:italic> strains. However, the function of MucR in the rough-type <jats:italic>Brucella canis<\/jats:italic> remains unknown. In this study, we discovered that MucR protein was involved in resistance to heat stress, iron-limitation, and various antibiotics in <jats:italic>B<\/jats:italic>. <jats:italic>canis<\/jats:italic>. In addition, the expression level of various bacterial flagellum-related genes was altered in <jats:italic>mucR<\/jats:italic> mutant strain. Deletion of this transcriptional regulator in <jats:italic>B. canis<\/jats:italic> significantly affected <jats:italic>Brucella<\/jats:italic> virulence in RAW264.7 macrophage and mice infection model. To gain insight into the genetic basis for distinctive phenotypic properties exhibited by <jats:italic>mucR<\/jats:italic> mutant strain, RNA-seq was performed and the result showed that various genes involved in translation, ribosomal structure and biogenesis, signal transduction mechanisms, energy production, and conversion were significantly differently expressed in \u0394<jats:italic>mucR<\/jats:italic> strain. Overall, these studies have not only discovered the phenotype of <jats:italic>mucR<\/jats:italic> mutant strain but also preliminarily uncovered the molecular mechanism between the transcriptional regulator MucR, stress response and bacterial virulence in <jats:italic>B<\/jats:italic>. <jats:italic>canis<\/jats:italic>.<\/jats:p>","DOI":"10.3389\/fvets.2021.650942","type":"journal-article","created":{"date-parts":[[2021,6,25]],"date-time":"2021-06-25T04:38:26Z","timestamp":1624595906000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":10,"title":["Deletion of the Transcriptional Regulator MucR in Brucella canis Affects Stress Responses and Bacterial Virulence"],"prefix":"10.3389","volume":"8","author":[{"given":"Jiali","family":"Sun","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Hao","family":"Dong","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Xiaowei","family":"Peng","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yufu","family":"Liu","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Hui","family":"Jiang","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yu","family":"Feng","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Qiaoling","family":"Li","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Liangquan","family":"Zhu","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yuming","family":"Qin","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jiabo","family":"Ding","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1965","published-online":{"date-parts":[[2021,6,25]]},"reference":[{"key":"B1","first-page":"604","article-title":"A 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