The complete open reading frame (ORF) of HIF1B and HIF2A gene were obtained and amino acid sequences were analyzed in Gymnocypris dobula and Schizothorax prenanti. In different tissues of G. dobula and S. prenanti, the mR-NA expression levels of HIF1B and HIF2A were assessed by fluorescence quantitative RT-PCR (qRT-PCR). Oreochromis niloticus was dealt with acute hypoxia (0. 5 h and 1 h), and the mRNA expression levels of HIF1B and HIF2A were ana-lyzed by qRT-PCR. The ORF of HIF1B in G. dobula and S. prenanti were 2 322 bp and 2 313 bp, and encoded 773 and 770 amino acids residues, respectively; The ORF of HIF2A gene were 2 466 bp and 2 502 bp, and encoded 821 and 833 amino acids residues, respectively. The homology of the ODD domain of HIF1B between G. dobula and S. prenanti were 93. 12%, and HIF2A were 89. 56%. A mutation ( LxxLAP to PxxLAP) was found in the conserved CODD domain of HIF1B in G. dobula (plateau schizothoracine fish). It may be a sign of functional evolution of HIF1B in plateau schizotho-racine fish. The qRT-PCR showed that the mRNA expression levels of HIF1B and HIF2A in teleost increased significantly in acute hypoxia, whereas decreased significantly in long-term hypoxia condition. We speculated that teleost may be have two different mechanisms to adapt to the acute hypoxia and long-term hypoxia condition, respectively.%获得高原软刺裸鲤(Gymnocypris dobula)和齐口裂腹鱼(Schizothorax prenanti)HIF1B和HIF2A基因cDNA完整的开放阅读框(ORF), 并进行氨基酸序列分析; 采用荧光定量PCR(qRT-PCR)技术, 检测了 HIF1B和HIF2A在两种裂腹鱼体内各组织中的表达, 以及应激性低氧条件下罗非鱼不同组织中的表达. 基因序列分析结果显示,软刺裸鲤和齐口裂腹鱼HIF1B基因长度分别为2 322 bp和2 313 bp, 预测编码773和770个氨基酸; HIF2A基因长度分别为2 466 bp和2 502 bp, 预测编码821和833个氨基酸. 同源分析显示, 齐口裂腹鱼和软刺裸鲤HIF1B ODD结构域氨基酸序列同源性为93. 12%, HIF2A为89. 56%. 在CODD保守结构域中,软刺裸鲤HIF1B的Lxx-LAP位点突变成PxxLAP,这可能是高原裂腹鱼HIF1B功能进化的重要标志. 定量检测结果表明,在应激性低氧环境中,硬骨鱼类鳃和皮肤中HIF1B和HIF2A mRNA的表达上升;而在长期低氧环境中,硬骨鱼类鳃和皮肤中HIF1B和HIF2A mRNA的表达下降,推测硬骨鱼体内可能存在两种不同的机制来适应长期低氧和应激性低氧环境.
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