{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,18]],"date-time":"2026-01-18T10:32:10Z","timestamp":1768732330337,"version":"3.49.0"},"reference-count":34,"publisher":"MDPI AG","issue":"13","license":[{"start":{"date-parts":[[2025,7,7]],"date-time":"2025-07-07T00:00:00Z","timestamp":1751846400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"National Natural Science Foundation of China","award":["32372701"],"award-info":[{"award-number":["32372701"]}]},{"name":"National Natural Science Foundation of China","award":["CARS-24-A-15"],"award-info":[{"award-number":["CARS-24-A-15"]}]},{"name":"China Agriculture Research System of MOF and MARA","award":["32372701"],"award-info":[{"award-number":["32372701"]}]},{"name":"China Agriculture Research System of MOF and MARA","award":["CARS-24-A-15"],"award-info":[{"award-number":["CARS-24-A-15"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>AT-hook motif nuclear-localized (AHL) genes play critical roles in chromatin remodeling and gene transcription regulation, profoundly influencing plant growth, development, and stress responses. While AHL genes have been extensively characterized in multiple plant species, their biological functions in pepper (Capsicum annuum L.) remain largely uncharacterized. In this study, we identified 45 CaAHL genes in the pepper genome through bioinformatics approaches. Comprehensive analyses were conducted to examine their chromosomal distribution, phylogenetic relationships, and the structural and functional features of their encoded proteins. Phylogenetic clustering classified the CaAHL proteins into six distinct subgroups. Transcriptome profiling revealed widespread expression of CaAHL genes across diverse tissues\u2014including roots, stems, leaves, flowers, seeds, pericarp, placenta, and fruits\u2014at various developmental stages. Quantitative real-time PCR further demonstrated that CaAHL1, CaAHL33, and CaAHL23 exhibited consistently high expression throughout flower bud development, whereas CaAHL36 showed preferential upregulation at early bud development stages. Expression profiling under hormone treatments and abiotic stresses indicated that CaAHL36 and CaAHL23 are auxin-inducible but are repressed by ABA, cold, heat, salt, and drought stress. Subcellular localization assays in Nicotiana benthamiana leaf epidermal cells showed that both CaAHL36 and CaAHL23 were predominantly localized in the nucleus, with faint expression also detected in the cytoplasm. Collectively, this study provides foundational insights into the CaAHL gene family, laying the groundwork for future functional investigations of these genes in pepper.<\/jats:p>","DOI":"10.3390\/ijms26136527","type":"journal-article","created":{"date-parts":[[2025,7,7]],"date-time":"2025-07-07T08:58:23Z","timestamp":1751878703000},"page":"6527","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Genome-Wide Identification and Analysis of the AHL Gene Family in Pepper (Capsicum annuum L.)"],"prefix":"10.3390","volume":"26","author":[{"given":"Xiao-Yan","family":"Sui","sequence":"first","affiliation":[{"name":"Key Laboratory for Vegetable Biology of Hunan Province, Engineering Research Center for Horticultural Crop Germplasm Creation and New Variety Breeding, Ministry of Education, College of Horticulture, Hunan Agricultural University, Changsha 410128, China"},{"name":"Yuelushan Laboratory, Changsha 410128, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yan-Long","family":"Li","sequence":"additional","affiliation":[{"name":"Key Laboratory for Vegetable Biology of Hunan Province, Engineering Research Center for Horticultural Crop Germplasm Creation and New Variety Breeding, Ministry of Education, College of Horticulture, Hunan Agricultural University, Changsha 410128, China"},{"name":"Yuelushan Laboratory, Changsha 410128, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Xi","family":"Wang","sequence":"additional","affiliation":[{"name":"Key Laboratory for Vegetable Biology of Hunan Province, Engineering Research Center for Horticultural Crop Germplasm Creation and New Variety Breeding, Ministry of Education, College of Horticulture, Hunan Agricultural University, Changsha 410128, China"},{"name":"Yuelushan Laboratory, Changsha 410128, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yi","family":"Zhong","sequence":"additional","affiliation":[{"name":"Key Laboratory for Vegetable Biology of Hunan Province, Engineering Research Center for Horticultural Crop Germplasm Creation and New Variety Breeding, Ministry of Education, College of Horticulture, Hunan Agricultural University, Changsha 410128, China"},{"name":"Yuelushan Laboratory, Changsha 410128, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Qing-Zhi","family":"Cui","sequence":"additional","affiliation":[{"name":"Key Laboratory for Vegetable Biology of Hunan Province, Engineering Research Center for Horticultural Crop Germplasm Creation and New Variety Breeding, Ministry of Education, College of Horticulture, Hunan Agricultural University, Changsha 410128, China"},{"name":"Yuelushan Laboratory, Changsha 410128, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0009-0009-3362-3195","authenticated-orcid":false,"given":"Yin","family":"Luo","sequence":"additional","affiliation":[{"name":"Yuelushan Laboratory, Changsha 410128, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Bing-Qian","family":"Tang","sequence":"additional","affiliation":[{"name":"Key Laboratory for Vegetable Biology of Hunan Province, Engineering Research Center for Horticultural Crop Germplasm Creation and New Variety Breeding, Ministry of Education, College of Horticulture, Hunan Agricultural University, Changsha 410128, China"},{"name":"Yuelushan Laboratory, Changsha 410128, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Feng","family":"Liu","sequence":"additional","affiliation":[{"name":"Key Laboratory for Vegetable Biology of Hunan Province, Engineering Research Center for Horticultural Crop Germplasm Creation and New Variety Breeding, Ministry of Education, College of Horticulture, Hunan Agricultural University, Changsha 410128, China"},{"name":"Yuelushan Laboratory, Changsha 410128, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Xue-Xiao","family":"Zou","sequence":"additional","affiliation":[{"name":"Key Laboratory for Vegetable Biology of Hunan Province, Engineering Research Center for Horticultural Crop Germplasm Creation and New Variety Breeding, Ministry of Education, College of Horticulture, Hunan Agricultural University, Changsha 410128, China"},{"name":"Yuelushan Laboratory, Changsha 410128, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2025,7,7]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"270","DOI":"10.1038\/ng.2877","article-title":"Genome sequence of the hot pepper provides insights into the evolution of pungency in Capsicum species","volume":"46","author":"Kim","year":"2014","journal-title":"Nat. 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