title: Molecular characterization and expression analysis of three hypoxia-inducible factor alpha subunits, HIF-1α/2α/3α of the hypoxia-sensitive freshwater species, Chinese sucker.
abstract: Hypoxia-inducible factors (HIFs) are transcription factors that respond to changes in oxygen tension in the cellular environment. In this study, we identified full-length cDNAs of HIF-1α, HIF-2α and HIF-3α in an endangered hypoxia-sensitive fish species, Chinese sucker. The HIF-1α/2α/3α cDNAs are 3890, 3230 and 3374 bp in length, encoding 780, 782 and 632 amino acid residues, respectively. The real-time PCR results suggested that HIF-1α and HIF-3α mRNAs were highly expressed in liver and gonads, followed by spleen and muscle. Moreover, HIF-1α and HIF-3α transcription factors revealed similar developmental expression patterns, with the lowest expression at 48h post-fertilization, and reaching the highest expression level at 360 h post-fertilization. Short-term hypoxia exposure (2.2, 2.8 and 3.2mg/L dissolved oxygen for 24h) increased mRNA levels of HIF-1α and HIF-3α. HIF-2α mRNA showed similar expression patterns with that of HIF-1α and HIF-3α, however, its expression was extremely low in the spatio-temporal expression patterns and hypoxia treatment. This is the first report describing the potential to identify hypoxia-sensitive/tolerant fishes according to the number of the serine residues of fish oxygen-dependent degradation (ODD) domain. It was suggested that Cyprinomorpha fishes, with less than 40 serine residues in fish ODD domain were hypoxia-sensitive fishes and more than 40 serine residues in this domain were hypoxia-tolerant fishes.
authors.affiliation: Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction, Ministry of Education, College of Fishery, Huazhong Agricultural University, 430070, Wuhan, PR China.
authors.forename: Nan
authors.initials: N
authors.lastname: Chen
authors.forename: Li Ping
authors.initials: LP
authors.lastname: Chen
authors.forename: Jie
authors.initials: J
authors.lastname: Zhang
authors.forename: Cheng
authors.initials: C
authors.lastname: Chen
authors.forename: Xin Lan
authors.initials: XL
authors.lastname: Wei
authors.forename: Yasmeen
authors.initials: Y
authors.lastname: Gul
authors.forename: Wei Min
authors.initials: WM
authors.lastname: Wang
authors.forename: Huan Ling
authors.initials: HL
authors.lastname: Wang
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D051792:Basic Helix-Loop-Helix Proteins / Q000235:genetics*; D002681:China; D003531:Cypriniformes / Q000235:genetics*; D017931:DNA Primers / Q000235:genetics; D029941:Fish Proteins / Q000235:genetics; D015870:Gene Expression; D000860:Hypoxia / Q000235:genetics; D051795:Hypoxia-Inducible Factor 1, alpha Subunit / Q000235:genetics*; D008969:Molecular Sequence Data; D010802:Phylogeny; D012333:RNA, Messenger / Q000235:genetics; D017386:Sequence Homology, Amino Acid; D000099162:Endothelial PAS Domain-Containing Protein 1
chemical_list: D051792:Basic Helix-Loop-Helix Proteins; D017931:DNA Primers; D029941:Fish Proteins; D051795:Hypoxia-Inducible Factor 1, alpha Subunit; D012333:RNA, Messenger; D000099162:Endothelial PAS Domain-Containing Protein 1