Download MendeleyStructure of dimeric lipoprotein lipase reveals a pore adjacent to the active site.
Gunn, K.H., Neher, S.B.(2023) Nat Commun 14: 2569-2569
- PubMed: 37142573
- DOI: https://doi.org/10.1038/s41467-023-38243-9
- Primary Citation of Related Structures:
8ERL - PubMed Abstract:
Lipoprotein lipase (LPL) hydrolyzes triglycerides from circulating lipoproteins, releasing free fatty acids. Active LPL is needed to prevent hypertriglyceridemia, which is a risk factor for cardiovascular disease (CVD). Using cryogenic electron microscopy (cryoEM), we determined the structure of an active LPL dimer at 3.9 Å resolution. This structure reveals an open hydrophobic pore adjacent to the active site residues. Using modeling, we demonstrate that this pore can accommodate an acyl chain from a triglyceride. Known LPL mutations that lead to hypertriglyceridemia localize to the end of the pore and cause defective substrate hydrolysis. The pore may provide additional substrate specificity and/or allow unidirectional acyl chain release from LPL. This structure also revises previous models on how LPL dimerizes, revealing a C-terminal to C-terminal interface. We hypothesize that this active C-terminal to C-terminal conformation is adopted by LPL when associated with lipoproteins in capillaries.
Organizational Affiliation:
Department of Biochemistry and Biophysics, University of North Carolina, Chapel Hill, NC, 27599, USA.
