{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,3]],"date-time":"2026-08-03T17:55:57Z","timestamp":1785779757845,"version":"3.56.0"},"reference-count":41,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2026,8,1]],"date-time":"2026-08-01T00:00:00Z","timestamp":1785542400000},"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":["U25A20727"],"award-info":[{"award-number":["U25A20727"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["32373170"],"award-info":[{"award-number":["32373170"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"award":["U25A20727"],"award-info":[{"award-number":["U25A20727"]}],"id":[{"id":"https:\/\/ror.org\/01h0zpd94","id-type":"ROR","asserted-by":"publisher"}]},{"award":["32373170"],"award-info":[{"award-number":["32373170"]}],"id":[{"id":"https:\/\/ror.org\/01h0zpd94","id-type":"ROR","asserted-by":"publisher"}]},{"name":"Southern Marine Science and Engineering Guangdong Laboratory","award":["SML2023SP237"],"award-info":[{"award-number":["SML2023SP237"]}]},{"award":["SML2023SP237"],"award-info":[{"award-number":["SML2023SP237"]}],"id":[{"id":"https:\/\/ror.org\/03swgqh13","id-type":"ROR","asserted-by":"publisher"}]},{"name":"Liaoning Provincial Natural Science Foundation General Project","award":["2024-MSLH-043"],"award-info":[{"award-number":["2024-MSLH-043"]}]},{"name":"Dalian High Level Talent Innovation Support Program","award":["2022RG14"],"award-info":[{"award-number":["2022RG14"]}]},{"name":"Dalian Outstanding Young Science and Technology Talent Program","award":["2024RJ010"],"award-info":[{"award-number":["2024RJ010"]}]},{"name":"The earmarked fund","award":["CARS-49"],"award-info":[{"award-number":["CARS-49"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Antioxidants"],"abstract":"<jats:p>Heat stress causes severe oxidative damage and immune cell death in marine bivalves, but its upstream regulators remain unclear. This study identified regulators linking heat stress to oxidative damage in Pacific oyster haemocytes. Under 30 \u00b0C exposure, the apoptosis rate of oyster haemocytes increased from ~4.54% to 17.40% at 24 h, accompanied by elevated ROS, malondialdehyde, and lipid hydroperoxide and reduced SOD activity. GSEA and protein interaction analysis of the haemocyte transcriptome pinpointed protein disulfide isomerase A6 (CgPDIA6) as the hub gene linking endoplasmic reticulum stress, apoptosis, and oxidative stress. Single-cell in silico knockout placed CgPDIA6 at the head of a coupled SOD\u2013peroxiredoxin relay (CgSOD1, CgSOD2, CgPRDX6) and shifted haemocytes toward a stress-activated state. This prediction was confirmed by RNAi knockdown, in which silencing CgPDIA6 aggravated heat-induced oxidative injury, reduced the expression of antioxidant-related genes (CgSOD1, CgSOD2, and CgPRDX6), and further suppressed SOD activity. Molecular dynamics simulations showed that heat destabilized its catalytic thioredoxin domains, compromising its protective function. These results demonstrate that CgPDIA6 protects haemocytes against heat-induced oxidative damage by sustaining antioxidant enzyme activity, providing insights into redox regulation and heat adaptation in mollusks.<\/jats:p>","DOI":"10.3390\/antiox15080963","type":"journal-article","created":{"date-parts":[[2026,8,3]],"date-time":"2026-08-03T17:26:52Z","timestamp":1785778012000},"page":"963","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Protein Disulfide Isomerase A6 (PDIA6) Restrains Heat-Induced Oxidative Damage in Haemocytes of the Pacific Oyster (Crassostrea gigas)"],"prefix":"10.3390","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0009-0009-0940-4638","authenticated-orcid":false,"given":"Pengcheng","family":"Sun","sequence":"first","affiliation":[{"name":"Liaoning Key Laboratory of Marine Animal Immunology & Disease Control, Dalian Ocean University, Dalian 116023, China"},{"name":"Dalian Key Laboratory of Aquatic Animal Disease Prevention and Control, Dalian Ocean University, Dalian 116023, China"},{"name":"Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai 519000, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ming","family":"Li","sequence":"additional","affiliation":[{"name":"College of Fisheries, Ocean University of China, Qingdao 266003, China"},{"name":"Zoneco Group Co., Ltd., Dalian 116001, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Peng","family":"Li","sequence":"additional","affiliation":[{"name":"Liaoning Key Laboratory of Marine Animal Immunology & Disease Control, Dalian Ocean University, Dalian 116023, China"},{"name":"Dalian Key Laboratory of Aquatic Animal Disease Prevention and Control, Dalian Ocean University, Dalian 116023, China"},{"name":"Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai 519000, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yang","family":"Ma","sequence":"additional","affiliation":[{"name":"Liaoning Key Laboratory of Marine Animal Immunology & Disease Control, Dalian Ocean University, Dalian 116023, China"},{"name":"Dalian Key Laboratory of Aquatic Animal Disease Prevention and Control, Dalian Ocean University, Dalian 116023, China"},{"name":"Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai 519000, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lei","family":"Gao","sequence":"additional","affiliation":[{"name":"Liaoning Key Laboratory of Marine Animal Immunology & Disease Control, Dalian Ocean University, Dalian 116023, China"},{"name":"Dalian Key Laboratory of Aquatic Animal Disease Prevention and Control, Dalian Ocean University, Dalian 116023, China"},{"name":"Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai 519000, China"},{"name":"Liaoning Key Laboratory of Marine Animal Immunology, Dalian Ocean University, Dalian 116023, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6473-5741","authenticated-orcid":false,"given":"Xueshu","family":"Zhang","sequence":"additional","affiliation":[{"name":"Liaoning Key Laboratory of Marine Animal Immunology & Disease Control, Dalian Ocean University, Dalian 116023, China"},{"name":"Dalian Key Laboratory of Aquatic Animal Disease Prevention and Control, Dalian Ocean University, Dalian 116023, China"},{"name":"Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai 519000, China"},{"name":"Liaoning Key Laboratory of Marine Animal Immunology, Dalian Ocean University, Dalian 116023, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1049-9170","authenticated-orcid":false,"given":"Lingling","family":"Wang","sequence":"additional","affiliation":[{"name":"Liaoning Key Laboratory of Marine Animal Immunology & Disease Control, Dalian Ocean University, Dalian 116023, China"},{"name":"Dalian Key Laboratory of Aquatic Animal Disease Prevention and Control, Dalian Ocean University, Dalian 116023, China"},{"name":"Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai 519000, China"},{"name":"Liaoning Key Laboratory of Marine Animal Immunology, Dalian Ocean University, Dalian 116023, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3580-6560","authenticated-orcid":false,"given":"Linsheng","family":"Song","sequence":"additional","affiliation":[{"name":"Liaoning Key Laboratory of Marine Animal Immunology & Disease Control, Dalian Ocean University, Dalian 116023, China"},{"name":"Dalian Key Laboratory of Aquatic Animal Disease Prevention and Control, Dalian Ocean University, Dalian 116023, China"},{"name":"Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai 519000, China"},{"name":"Liaoning Key Laboratory of Marine Animal Immunology, Dalian Ocean University, Dalian 116023, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,8,1]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"155478","DOI":"10.1016\/j.scitotenv.2022.155478","article-title":"Alongshore upwelling modulates the intensity of marine heatwaves in a temperate coastal sea","volume":"835","author":"Izquierdo","year":"2022","journal-title":"Sci. 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