6L1D

Structure of human StAR-related lipid transfer protein 4

6L1D の概要

• エントリーDOI: 10.2210/pdb6l1d/pdb
• 分子名称: StAR-related lipid transfer protein 4 (2 entities in total)
• 機能のキーワード: stard4, lipid transport, sterol, cholesterol, lipid transfer protein, transport protein
• 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: 47770.00

構造登録者

Tong, J.,Im, Y.J. (登録日: 2019-09-29, 公開日: 2019-10-30, 最終更新日: 2023-11-22)

主引用文献

Tan, L.,Tong, J.,Chun, C.,Im, Y.J.
Structural analysis of human sterol transfer protein STARD4.
Biochem.Biophys.Res.Commun., 520:466-472, 2019

PubMed Abstract: The steroidogenic acute regulatory protein (StAR)-related lipid transfer domain-4 (STARD4) is a sterol-binding protein that is involved in cholesterol homeostasis by intracellular sterol transport. In this work, we determined the crystal structures of human STARD4 and its Ω1-loop mutant in apo forms at 1.95 and 1.7 Å resolutions, respectively. The structure of human STARD4 displays a conserved α-helix/β-grip fold containing a deep hydrophobic pocket. The Ω1-loop which serves as a lid for the hydrophobic pocket has a closed conformation. The shape of the sterol-binding cavity in the closed form is not complementary to accommodate cholesterol, suggesting that a conformational change of the Ω1-loop is essential for sterol binding. The human STARD4 displayed sterol transfer activity between liposomes, and the mutations in the Ω1-loop and the hydrophobic wall abolished the transfer activity. This study confirms the structural conservation of the STARD4 subfamily proteins and the flexibility of the Ω1-loop and helix α4 required for sterol transport.

PubMed: 31607485
DOI: 10.1016/j.bbrc.2019.10.054

実験手法

X-RAY DIFFRACTION (1.95 Å)