摘要: |
胃质子泵(H+/K+ ATPase)是胃酸分泌的关键酶。本试验采用RACE 和PCR 方法从大菱鲆的胃组织中提取RNA克隆得到了H+/K+ ATPase α亚基cDNA全长序列。结果表明: 大菱鲆H+/K+ ATPase α亚基序列全长3467 bp, 开放阅读框为2964 bp, 编码988 个氨基酸。与GenBank 上其它物种比对发现, 大菱鲆H+/K+ ATPase α亚基与斑鳜同源性最高, 为89%。进化树分析发现, H+/K+ ATPase 在进化上具有物种特异性。经RT-PCR 和荧光定量PCR 检测, 大菱鲆H+/K+ ATPase 在胚胎孵化后22d 开始表达, 晚于大菱鲆胃腺出现的时间(16 d), 说明大菱鲆胃腺的发育完成并不代表胃功能的完善。另外, 大菱鲆H+/K+ ATPase 除了在胃中大量表达之外, 在食道中的表达量也很高。结合组织学观察,作者认为, 大菱鲆H+/K+ ATPase 在食道中大量表达是因为在发育上食道是胃的前体, 因此保留了分泌H+/K+ ATPase 的能力。同时通过整体原位杂交试验表明: 大菱鲆H+/K+ ATPase 会首先在食道的末端和胃的贲门处表达。本研究为进一步了解海水鱼类的消化机制提供了理论基础。 |
关键词: 大菱鲆 胃质子泵 组织表达 消化 |
DOI:10.11693/hyhz20130306001 |
分类号: |
基金项目:现代农业产业技术体系建设专项资金, nycytx-50 号 |
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ACID DIGESTION IN TURBOT SCOPHTHALMUS MAXIMUS BASED ON H+ /K+ ATPase |
chiliang
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institute of oceanology,Chinese academy of sciences
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Abstract: |
Gastric proton pump (H+/K+ ATPase) is a key enzyme involved in gastric acid secretion. We isolated a full-length cDNA sequence of α subunit of H+/K+ ATPase from gastric tissue of turbot Scophthalmus maximus through RT-PCR and RACE (Rapid amplification of cDNA ends). Results indicate that H+/K+ ATPase cDNA was 3467 bp from which 988 amino acids were deduced. The nucleotied sequence of on subunit of H+/K+ ATPase shared high homology with
Siniperca chautsi (89%). Phylogenetic analysis showed that H+/K+ ATPase was species-specific in evolution. The initial transcripts H+/K+ ATPase were detected in 22 days post hatching (dph), after gastric glands (16 dph) were formed. This suggested that the morphologic development of gastric glands was not synchronous with their functional development. In addition, H+/K+ ATPase mRNAs were expressed highly in esophagus. We surmised that the turbot stomach was reduced to a dilatation of esophagus, and that esophagus retained its ability to express pepsinogen. The distribution of tPGA and tPGC transcripts in the turbot was investigated using in-situ hybridization. The results show that tPGA and tPGC mRNA were first detected in the esophagus and cardiac region of the stomach. This study provided a basis for understanding the digestive mechanisms in teleost. |
Key words: Scophthalmus maximus H+ /K+ ATPase expression analysis digestion |