1W2C

Human Inositol (1,4,5) trisphosphate 3-kinase complexed with Mn2+/AMPPNP/Ins(1,4,5)P3

1W2C の概要

• エントリーDOI: 10.2210/pdb1w2c/pdb
• 関連するPDBエントリー: 1W2D 1W2F
• 分子名称: INOSITOL-TRISPHOSPHATE 3-KINASE A, PHOSPHOAMINOPHOSPHONIC ACID-ADENYLATE ESTER, D-MYO-INOSITOL-1,4,5-TRIPHOSPHATE, ... (6 entities in total)
• 機能のキーワード: inositol phosphate kinase, amppnp, ip3, transferase
• 由来する生物種: HOMO SAPIENS (HUMAN)
• タンパク質・核酸の鎖数: 2
• 化学式量合計: 63101.95

構造登録者

Gonzalez, B.,Schell, M.J.,Irvine, R.F.,Williams, R.L. (登録日: 2004-07-01, 公開日: 2004-09-09, 最終更新日: 2024-05-08)

主引用文献

Gonzalez, B.,Schell, M.J.,Letcher, A.J.,Veprintsev, D.B.,Irvine, R.F.,Williams, R.L.
Structure of a Human Inositol 1,4,5-Trisphosphate 3-Kinase; Substrate Binding Reveals Why It is not a Phosphoinositide 3-Kinase
Mol.Cell, 15:689-, 2004

PubMed Abstract: Mammalian cells produce a variety of inositol phosphates (InsPs), including Ins(1,4,5)P3 that serves both as a second messenger and as a substrate for inositol polyphosphate kinases (IPKs), which further phosphorylate it. We report the structure of an IPK, the human Ins(1,4,5)P3 3-kinase-A, both free and in complexes with substrates and products. This enzyme catalyzes transfer of a phosphate from ATP to the 3-OH of Ins(1,4,5)P3, and its X-ray crystal structure provides a template for understanding a broad family of InsP kinases. The catalytic domain consists of three lobes. The N and C lobes bind ATP and resemble protein and lipid kinases, despite insignificant sequence similarity. The third lobe binds inositol phosphate and is a unique four-helix insertion in the C lobe. This lobe embraces all of the phosphates of Ins(1,4,5)P3 in a positively charged pocket, explaining the enzyme's substrate specificity and its inability to phosphorylate PtdIns(4,5)P2, the membrane-resident analog of Ins(1,4,5)P3.

PubMed: 15350214
DOI: 10.1016/J.MOLCEL.2004.08.004

実験手法

X-RAY DIFFRACTION (1.95 Å)