6U7M

Cryo-EM Structure of Helical Lipoprotein Lipase

6U7M の概要

• エントリーDOI: 10.2210/pdb6u7m/pdb
• EMDBエントリー: 20673
• 分子名称: Lipoprotein lipase (1 entity in total)
• 機能のキーワード: helical symmetry, lipoprotein lipase, protein fibril, hydrolase
• 由来する生物種: Bos taurus (Bovine)
• タンパク質・核酸の鎖数: 30
• 化学式量合計: 1603463.67

構造登録者

Gunn, K.H.,Wang, F.,Egelman, E.H.,Neher, S.B. (登録日: 2019-09-03, 公開日: 2020-04-08, 最終更新日: 2025-05-21)

主引用文献

Gunn, K.H.,Roberts, B.S.,Wang, F.,Strauss, J.D.,Borgnia, M.J.,Egelman, E.H.,Neher, S.B.
The structure of helical lipoprotein lipase reveals an unexpected twist in lipase storage.
Proc.Natl.Acad.Sci.USA, 117:10254-10264, 2020

PubMed Abstract: Lipases are enzymes necessary for the proper distribution and utilization of lipids in the human body. Lipoprotein lipase (LPL) is active in capillaries, where it plays a crucial role in preventing dyslipidemia by hydrolyzing triglycerides from packaged lipoproteins. Thirty years ago, the existence of a condensed and inactive LPL oligomer was proposed. Although recent work has shed light on the structure of the LPL monomer, the inactive oligomer remained opaque. Here we present a cryo-EM reconstruction of a helical LPL oligomer at 3.8-Å resolution. Helix formation is concentration-dependent, and helices are composed of inactive dihedral LPL dimers. Heparin binding stabilizes LPL helices, and the presence of substrate triggers helix disassembly. Superresolution fluorescent microscopy of endogenous LPL revealed that LPL adopts a filament-like distribution in vesicles. Mutation of one of the helical LPL interaction interfaces causes loss of the filament-like distribution. Taken together, this suggests that LPL is condensed into its inactive helical form for storage in intracellular vesicles.

PubMed: 32332168
DOI: 10.1073/pnas.1916555117

実験手法

ELECTRON MICROSCOPY (3.8 Å)