欖綠青蟳 (Scylla olivacea) 中甲殼類升血糖荷爾蒙異構型蛋白質(Sco-CHH-L)是屬於甲殼類升血糖荷爾蒙家族之一成員，其蛋白質結構和生理功能及重要胺基酸調控功能未點位點尚未被證實。本篇研究利用核磁共振光譜技術解出此甲殼類升血糖荷爾蒙異構型蛋白質，進而探討其結構與功能之間的關聯性。 根據解析出的甲殼類升血糖荷爾蒙異構型蛋白質結構特徵與生化功能結果，提出N端及C端重要功能胺基酸位點。 生理功能研究顯示重組甲殼類升血糖荷爾蒙異構型蛋白質能增加腮組織中鈉鉀泵的活性。 並將甲殼類升血糖荷爾蒙異構型蛋白質進行點突變實驗建構出突變株進行體外鈉鉀泵的活性研究。結果顯示會影響鈉鉀泵的活性表現的胺基酸是位於蛋白質結構中π-helix區域和C端區域。本研究利用核磁共振光譜技術解出第一個 Type I甲殼類升血糖荷爾蒙家族中甲殼類升血糖荷爾蒙異構型蛋白質結構，功能研究發現甲殼類升血糖荷爾蒙異構型蛋白質主要是調控鈉鉀泵的活性，並發現其重要的功能胺基酸位點。

The Scylla olivacea crustacean hyperglycemic hormone-like (Sco-CHH-L) peptide belongs to the crustacean hyperglycemic hormone (CHH) family, but its function, specific binding sites, and structure have not been reported. To explore the structure–function relationship of the Sco-CHH-L peptide, the solution structure of Sco-CHH-L was determined through heteronuclear three-dimensional nuclear magnetic resonance spectrometry in our study. Based on the tertiary structure and biochemical assay results, we propose functionally vital residues in the N and C termini of the Sco-CHH-L peptide derived from S. olivacea, the mud crab. Physiological function analysis showed that the recombinant Sco-CHH-L peptide increased Na+, K+-ATPase activity in the gill. To investigate biologically vital residues of the Sco-CHH-L peptide, both wild-type and point-mutated Sco-CHH-L peptides were constructed. The recombinant peptides were tested using an in-vivo Na+, K+-ATPase activity assay. The assay results indicated residues in π-helix region or C-terminus of Sco-CHH-L affected Na+, K+-ATPase activity. The function analysis results revealed that Sco-CHH-L from S. olivacea is involved in the stimulation of Na+, K+-ATPase activity in crustaceans. In this paper, we provide the first Type I CHH family solution structure, information on the functional importance of residues in Sco-CHH-L, and the effect on Na+-, K+-ATPase activity in crustaceans.

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