title: Identification of HIF-1 signaling pathway in Pelteobagrus vachelli using RNA-Seq: effects of acute hypoxia and reoxygenation on oxygen sensors, respiratory metabolism, and hematology indices.
abstract: Oxygen is a vital element in aquatic environments. The concentration of oxygen to which aquatic organisms are exposed is influenced by salinity, water temperature, weather, and surface water runoff. Hypoxia has a serious effect on fish populations, and can lead to the loss of habitat and die-offs. Therefore, in the present study we used next-generation sequencing technology to characterize the transcriptomes of Pelteobagrus vachelli and identified 70 candidate genes in the HIF-1 signaling pathway that are important for the hypoxic response in all metazoan species. For the first time, the present study reported the effects of acute hypoxia and reoxygenation on oxygen sensors, respiratory metabolism, and hematology indices in P. vachelli. The predicted physiological adjustments show that P. vachelli's blood oxygen-carrying capacity was increased through increased RBC, HB, and SI after hypoxia exposure. Glycolysis-related enzyme activities (PFK, HK, and PK) and LDH in the brain and liver also increased, indicating a rise in anaerobic metabolism. The observed reduction in oxidative enzyme level (CS) in the liver during hypoxia suggests a concomitant depression in aerobic metabolism. There were significant increases in oxygen sensor mRNA expression and HIF-1α protein expression during hypoxia and reoxygenation exposure, suggesting that the HIF-1 signaling pathway was activated in the liver and brain of P. vachelli in response to acute hypoxia and reoxygenation. Our findings suggest that oxygen sensors (e.g., HIF-1α) of P. vachelli are potentially useful biomarkers of environmental hypoxic exposure. These data contribute to a better understanding of the molecular mechanisms of the hypoxia signaling pathway in fish under hypoxia and reoxygenation.
authors.affiliation: College of Life Sciences, Key Laboratory of Biodiversity and Biotechnology of Jiangsu Province, Nanjing Normal University, 1 Wenyuan Road, Nanjing, 210023, Jiangsu, China.|Co-Innovation Center for Marine Bio-Industry Technology of Jiangsu Province, Lianyungang, 222005, Jiangsu, China.
authors.forename: Guosong
authors.initials: G
authors.lastname: Zhang
authors.affiliation: College of Life Sciences, Key Laboratory of Biodiversity and Biotechnology of Jiangsu Province, Nanjing Normal University, 1 Wenyuan Road, Nanjing, 210023, Jiangsu, China.|Co-Innovation Center for Marine Bio-Industry Technology of Jiangsu Province, Lianyungang, 222005, Jiangsu, China.
authors.forename: Cheng
authors.initials: C
authors.lastname: Zhao
authors.affiliation: College of Life Sciences, Key Laboratory of Biodiversity and Biotechnology of Jiangsu Province, Nanjing Normal University, 1 Wenyuan Road, Nanjing, 210023, Jiangsu, China.
authors.forename: Qintao
authors.initials: Q
authors.lastname: Wang
authors.affiliation: College of Life Sciences, Key Laboratory of Biodiversity and Biotechnology of Jiangsu Province, Nanjing Normal University, 1 Wenyuan Road, Nanjing, 210023, Jiangsu, China.
authors.forename: Yichun
authors.initials: Y
authors.lastname: Gu
authors.affiliation: College of Life Sciences, Key Laboratory of Biodiversity and Biotechnology of Jiangsu Province, Nanjing Normal University, 1 Wenyuan Road, Nanjing, 210023, Jiangsu, China.
authors.forename: Zecheng
authors.initials: Z
authors.lastname: Li
authors.affiliation: College of Life Sciences, Key Laboratory of Biodiversity and Biotechnology of Jiangsu Province, Nanjing Normal University, 1 Wenyuan Road, Nanjing, 210023, Jiangsu, China.
authors.forename: Panfeng
authors.initials: P
authors.lastname: Tao
authors.affiliation: College of Life Sciences, Key Laboratory of Biodiversity and Biotechnology of Jiangsu Province, Nanjing Normal University, 1 Wenyuan Road, Nanjing, 210023, Jiangsu, China.
authors.forename: Jiawei
authors.initials: J
authors.lastname: Chen
authors.affiliation: College of Life Sciences, Key Laboratory of Biodiversity and Biotechnology of Jiangsu Province, Nanjing Normal University, 1 Wenyuan Road, Nanjing, 210023, Jiangsu, China. yinshaowu@hotmail.com.|Co-Innovation Center for Marine Bio-Industry Technology of Jiangsu Province, Lianyungang, 222005, Jiangsu, China. yinshaowu@hotmail.com.
authors.forename: Shaowu
authors.identifier: http://orcid.org/0000-0002-0269-2077
authors.initials: S
authors.lastname: Yin
mesh_terms: D000222:Adaptation, Physiological; D000818:Animals; D001921:Brain / Q000378:metabolism; D002397:Catfishes / Q000097:blood / Q000235:genetics / Q000378:metabolism*; D004734:Energy Metabolism; D029941:Fish Proteins / Q000235:genetics / Q000378:metabolism*; D015971:Gene Expression Regulation, Enzymologic; D000860:Hypoxia / Q000097:blood / Q000235:genetics / Q000378:metabolism*; D051795:Hypoxia-Inducible Factor 1, alpha Subunit / Q000235:genetics / Q000378:metabolism*; D008099:Liver / Q000378:metabolism; D010100:Oxygen / Q000097:blood / Q000378:metabolism*; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism*; D017423:Sequence Analysis, RNA; D015398:Signal Transduction; D013997:Time Factors
chemical_list: D029941:Fish Proteins; D051795:Hypoxia-Inducible Factor 1, alpha Subunit; D012333:RNA, Messenger; D010100:Oxygen
keywords: Hematology indices; Hypoxia; Oxygen sensors; Pelteobagrus vachelli; Reoxygenation; Respiratory metabolism