{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,7]],"date-time":"2026-05-07T08:10:51Z","timestamp":1778141451583,"version":"3.51.4"},"reference-count":39,"publisher":"Portland Press Ltd.","issue":"6","license":[{"start":{"date-parts":[[2026,4,15]],"date-time":"2026-04-15T00:00:00Z","timestamp":1776211200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["portlandpress.com"],"crossmark-restriction":true},"short-container-title":[],"published-print":{"date-parts":[[2026,6,3]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:p>Small protein B (SmpB) is a key regulator of trans-translation in bacteria. The interactome of Mycobacterium tuberculosis (Mtb) ClpX revealed SmpB alongside multiple transcriptional regulators and \u03c3 factors that can alter the transcriptional profile. The finding that ClpX could also be identified in the Mtb SmpB interactome suggested both physical and functional linkages between trans-translation and targeted protein degradation. The trans-translation mechanism facilitates the release of stalled ribosomes and the attachment of ssrA degron sequences to aberrant proteins. We show that both SmpB and the previously described Mtb ClpX adaptor, single-stranded DNA binding protein (SSB), bind to the N-terminal domain of ClpX. However, unlike the adaptor SSB, SmpB binding does not enhance ClpX ATPase activity. Interaction studies using a model substrate with an exposed ssrA degron revealed that SmpB enhances ClpX\u2013substrate interactions. ClpX unfoldase activity, on the other hand, enables targeted degradation of proteins containing the ssrA degron. ClpX also facilitates the release of specific \u03c3 factors from inactive \u03c3\/anti-\u03c3 complexes by degrading anti-\u03c3 factors containing the ssrA degron, thus indirectly influencing the transcription profile. Together, these observations suggest that SmpB and ClpX interactions and interacting protein networks exert both direct and indirect effects on the Mtb transcriptional profile.<\/jats:p>","DOI":"10.1042\/bcj20253192","type":"journal-article","created":{"date-parts":[[2026,4,15]],"date-time":"2026-04-15T12:33:40Z","timestamp":1776256420000},"page":"833-848","update-policy":"https:\/\/doi.org\/10.1042\/crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Influence of SmpB and ClpX interactions and interactomes on the transcription profile of\n                    <i>Mycobacterium tuberculosis<\/i>"],"prefix":"10.1042","volume":"483","author":[{"given":"Ashish","family":"Deshmukh","sequence":"first","affiliation":[{"name":"1Molecular Biophysics Unit, Indian Institute of Science, Bangalore, India"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Sidra","family":"Khan","sequence":"additional","affiliation":[{"name":"2CSIR-Centre for Cellular and Molecular Biology, Hyderabad, India"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Amit","family":"Chakraborty","sequence":"additional","affiliation":[{"name":"2CSIR-Centre for Cellular and Molecular Biology, Hyderabad, India"},{"name":"3Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, India"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5682-4178","authenticated-orcid":false,"given":"Vinay","family":"Nandicoori","sequence":"additional","affiliation":[{"name":"2CSIR-Centre for Cellular and Molecular Biology, Hyderabad, India"},{"name":"3Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, India"},{"name":"4National Institute of Immunology, New Delhi, India"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9097-5052","authenticated-orcid":false,"given":"Balasubramanian","family":"Gopal","sequence":"additional","affiliation":[{"name":"1Molecular Biophysics Unit, Indian Institute of Science, Bangalore, India"},{"name":"5Institute of Bioinformatics and Applied Biotechnology, Bangalore, India"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"288","published-online":{"date-parts":[[2026,5,7]]},"reference":[{"key":"2026050703165730600_B1","doi-asserted-by":"publisher","first-page":"3793","DOI":"10.1093\/emboj\/18.13.3793","article-title":"SmpB, a unique RNA-binding protein essential for the peptide-tagging activity of SsrA (tmRNA)","volume":"18","author":"Karzai","year":"1999","journal-title":"EMBO J."},{"key":"2026050703165730600_B2","doi-asserted-by":"publisher","first-page":"257","DOI":"10.1016\/j.cell.2011.03.036","article-title":"Single-molecule protein unfolding and translocation by an ATP-fueled proteolytic machine","volume":"145","author":"Aubin-Tam","year":"2011","journal-title":"Cell"},{"key":"2026050703165730600_B3","doi-asserted-by":"publisher","first-page":"459","DOI":"10.1016\/j.cell.2011.04.010","article-title":"ClpX(P) generates mechanical force to unfold and translocate its protein substrates","volume":"145","author":"Maillard","year":"2011","journal-title":"Cell"},{"key":"2026050703165730600_B4","doi-asserted-by":"publisher","first-page":"15","DOI":"10.1016\/j.bbamcr.2011.06.007","article-title":"ClpXP, an ATP-powered unfolding and protein-degradation machine","volume":"1823","author":"Baker","year":"2012","journal-title":"Biochim. 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