{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,24]],"date-time":"2026-08-24T04:19:57Z","timestamp":1787545197242,"version":"build-2736575974"},"reference-count":43,"publisher":"MDPI AG","issue":"16","license":[{"start":{"date-parts":[[2026,8,21]],"date-time":"2026-08-21T00:00:00Z","timestamp":1787270400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["32172546"],"award-info":[{"award-number":["32172546"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"award":["32172546"],"award-info":[{"award-number":["32172546"]}],"id":[{"id":"https:\/\/ror.org\/01h0zpd94","id-type":"ROR","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Int. J. Mol. Sci.","IJMS"],"abstract":"<jats:p>The Bcl-2-associated athanogene (BAG) gene family plays vital roles in plant growth, development, and biotic and abiotic stress responses. Previous work has demonstrated that tomato SlBAG9, a group II BAG member, negatively regulates plant thermotolerance. However, the regulatory mechanisms governing SlBAG9 expression remain poorly understood. In this study, we isolated and characterized the authentic 1486 bp full-length promoter (P1) of SlBAG9 from the tomato genome. Building upon our previous transcript-level observations, we provide here a detailed functional characterization of this promoter at the cellular and tissue level. In silico analysis identified several key cis-acting regulatory elements, including abscisic acid-responsive elements (ABRE), anaerobic response elements (ARE), and a heat shock element (HSE1). We used stable transgenic tomato plants carrying SlBAG9pro::GUS to verify that the full-length promoter was capable of driving the expression of \u03b2-glucuronidase reporter gene (GUS) in transgenic tomato plants, showing GUS staining was detectable in the roots, stems, leaves, flowers, fruits, and seeds, with the highest activity in red-ripe fruits. Notably, GUS activity was significantly upregulated by high temperature (HT) but not by PEG, NaCl, ABA, or cold treatments. To further dissect the HT-responsive regulatory module, we generated three 5\u2032-terminal deletion fragments (\u2212386 bp, P2; \u2212239 bp, P3; and \u2212113 bp, P4) and fused them to GUS. Under HT stress, the smallest deletion P4 showed negligible GUS activity, whereas P1, P2, and P3 retained significant activity. Furthermore, site-directed deletion of the HSE1 element in the full-length context (MU-P1) abolished HT inducibility, confirming that HSE1 serves as a critical positive HT-responsive element. Collectively, these findings confirm and extend our observations that SlBAG9 is a stress-responsive gene, and the characterized HSE1-dependent promoter module represents a promising candidate for genetic engineering aimed at enhancing thermotolerance in crops.<\/jats:p>","DOI":"10.3390\/ijms27167496","type":"journal-article","created":{"date-parts":[[2026,8,21]],"date-time":"2026-08-21T15:51:05Z","timestamp":1787327465000},"page":"7496","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Molecular Dissection of the SlBAG9 Promoter from Tomato and Its Thermo-Regulatory Activity"],"prefix":"10.3390","volume":"27","author":[{"given":"Fan","family":"Fei","sequence":"first","affiliation":[{"name":"College of Bioscience and Biotechnology, Yangzhou University, Yangzhou 225009, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Fan","family":"Yang","sequence":"additional","affiliation":[{"name":"College of Bioscience and Biotechnology, Yangzhou University, Yangzhou 225009, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yucheng","family":"Peng","sequence":"additional","affiliation":[{"name":"College of Landscape and Horticulture, Yangzhou University, Yangzhou 225009, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Menghan","family":"Zhu","sequence":"additional","affiliation":[{"name":"College of Bioscience and Biotechnology, Yangzhou University, Yangzhou 225009, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sihan","family":"Li","sequence":"additional","affiliation":[{"name":"College of Bioscience and Biotechnology, Yangzhou University, Yangzhou 225009, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hailong","family":"Jiang","sequence":"additional","affiliation":[{"name":"College of Bioscience and Biotechnology, Yangzhou University, Yangzhou 225009, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0644-238X","authenticated-orcid":false,"given":"Haidong","family":"Ding","sequence":"additional","affiliation":[{"name":"College of Bioscience and Biotechnology, Yangzhou University, Yangzhou 225009, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,8,21]]},"reference":[{"key":"ref_1","first-page":"1455","article-title":"Review on plant gene promoters","volume":"31","author":"Zhang","year":"2004","journal-title":"Acta Genet. 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