2GLG

NMR structure of the [L23,A24]-sCT mutant

2GLG の概要

• エントリーDOI: 10.2210/pdb2glg/pdb
• 関連するPDBエントリー: 2GLH
• 分子名称: Calcitonin-1 (1 entity in total)
• 機能のキーワード: a-helix, hormone-growth factor complex, hormone/growth factor
• 細胞内の位置: Secreted: P01263
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 3366.82

構造登録者

Andreotti, G.,Lopez-Mendez, B.,Amodeo, P.,Morelli, M.A.,Nakamuta, H.,Motta, A. (登録日: 2006-04-04, 公開日: 2006-06-20, 最終更新日: 2024-11-13)

主引用文献

Andreotti, G.,Mendez, B.L.,Amodeo, P.,Morelli, M.A.,Nakamuta, H.,Motta, A.
Structural determinants of salmon calcitonin bioactivity: the role of the Leu-based amphipathic alpha-helix.
J.Biol.Chem., 281:24193-24203, 2006

PubMed Abstract: Salmon calcitonin (sCT) forms an amphipathic helix in the region 9-19, with the C-terminal decapeptide interacting with the helix (Amodeo, P., Motta, A., Strazzullo, G., Castiglione Morelli, M. A. (1999) J. Biomol. NMR 13, 161-174). To uncover the structural requirements for the hormone bioactivity, we investigated several sCT analogs. They were designed so as to alter the length of the central helix by removal and/or replacement of flanking residues and by selectively mutating or deleting residues inside the helix. The helix content was assessed by circular dichroism and NMR spectroscopies; the receptor binding affinity in human breast cancer cell line T 47D and the in vivo hypocalcemic activity were also evaluated. In particular, by NMR spectroscopy and molecular dynamics calculations we studied Leu(23),Ala(24)-sCT in which Pro(23) and Arg(24) were replaced by helix inducing residues. Compared with sCT, it assumes a longer amphipathic alpha-helix, with decreased binding affinity and one-fifth of the hypocalcemic activity, therefore supporting the idea of a relationship between a definite helix length and bioactivity. From the analysis of other sCT mutants, we inferred that the correct helix length is located in the 9-19 region and requires long range interactions and the presence of specific regions of residues within the sequence for high binding affinity and hypocalcemic activity. Taken together, the structural and biological data identify well defined structural parameters of the helix for sCT bioactivity.

PubMed: 16766525
DOI: 10.1074/jbc.M603528200

実験手法

SOLUTION NMR