Oxygen-binding proteins, such as myoglobin, hemoglobin, neuroglobin, and cytoglobin, play a role in oxygen binding and delivery to tissues. In icefish, the loss of myoglobin and hemoglobin genes has been reported to be an adaptive evolution event. This interesting finding prompted us to exam oxygen-binding protein expression in diverse fish species. Taking advantage of substantial RNAseq data deposited in the NCBI (National Center for Biotechnology Information) database, we adopted a meta-transcriptomic approach to explore and compare four oxygen-binding protein gene expression levels in the skeletal muscle of 25 diverse fish species for the first time. RNAseq data were downloaded from the NCBI Sequence Read Archive (SRA) database, and de novo assembly was performed to generate transcript contigs. The genes encoding oxygen-binding proteins were then identified by the BLAST search, and the relative expression level of oxygen-binding protein genes was normalized by the RPKM (Reads per Kilobase Million) method. By performing expression profiling, hierarchy clustering, and principal component analysis, pacu and loach fish were noticed by their high myoglobin expression levels in skeletal muscle tissues among 25 diverse fish species. In conclusion, we demonstrated that meta-transcriptomic analysis of RNAseq data is an informative approach to compare the oxygen-binding protein expression and putative gene expansion event in fish.

中文翻译：

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RNAseq数据的亚转录组学分析揭示了Pacu和泥ach鱼骨骼肌中肌红蛋白表达异常高。

氧结合蛋白，例如肌红蛋白，血红蛋白，神经血红蛋白和细胞血红蛋白，在氧结合和向组织的输送中发挥作用。在冰鱼中，据报道肌红蛋白和血红蛋白基因的丧失是一种适应性进化事件。这一有趣的发现促使我们检查了多种鱼类中氧结合蛋白的表达。利用存储在NCBI（国家生物技术信息中心）数据库中的大量RNAseq数据，我们采用了元转录组学方法来探索和比较25种不同鱼类的骨骼肌中四种氧结合蛋白基因的表达水平。时间。从NCBI序列读取档案（SRA）数据库下载RNAseq数据，然后从头进行组装以生成转录本重叠群。然后通过BLAST搜索鉴定编码氧结合蛋白的基因，并通过RPKM（每千碱基百万读数）方法对氧结合蛋白基因的相对表达水平进行标准化。通过执行表达谱分析，层次聚类和主成分分析，pacu和泥ach鱼在25种不同鱼类中骨骼肌组织中的高肌红蛋白表达水平被注意到。总之，我们证明了RNAseq数据的转录组分析是一种比较鱼类中氧结合蛋白表达和推定基因扩增事件的有益方法。和主要成分分析发现，pacu和泥ach鱼在25种鱼类中骨骼肌组织中的高肌红蛋白表达水平很高。总之，我们证明了RNAseq数据的转录组分析是一种比较鱼类中氧结合蛋白表达和推定基因扩增事件的有益方法。和主要成分分析发现，pacu和泥ach鱼在25种鱼类中骨骼肌组织中的高肌红蛋白表达水平很高。总之，我们证明了RNAseq数据的转录组分析是一种比较鱼类中氧结合蛋白表达和推定基因扩增事件的有益方法。