We FRET so You Don't Have To: New Models of the Lipoprotein Lipase Dimer

作者：Hayne Cassandra K; Yumerefendi Hayretin; Cao Lin; Gauer Jacob W; Lafferty Michael J; Kuhlman Brian; Erie Dorothy A; Neher Saskia B^*

来源：Biochemistry, 2018, 57(2): 241-254.

DOI：10.1021/acs.biochem.7b01009

Lipoprotein lipase (LPL) is a dimeric enzyme that is responsible for clearing triglyceride-rich lipoproteins from the blood. Although LPL plays a key role in cardiovascular health, an experimentally derived,three-dimensional structure has not been determined. Such a structure would aid in understanding mutations in LPL that cause familial LPL deficiency in-patients and help in the development of therapeutic strategies to target LPL. A major obstacle to structural studies LPL is that LPL is an unstable protein that is difficult to produce in the quantities needed: or nuclear magnetic resonance or crystallography. We present updated LPL structural models generated by combining disulfide mapping, computational modeling, and data derived from single-molecule Forster resonance energy transfer (smFRET). We pioneer the technique of smFRET for use with LPL by developing conditions for imaging active LPL and identifying positions in LPL for the attachment of fluorophores. Using this approach, we measure LPL-LPL intermolecular interactions to generate experimental constraints that inform new computational Models of the LPL dimer structure. These models suggest that LPL may dimerize using an interface that is different from the dimerization interface suggested by crystal packing contacts seen in Structures of pancreatic lipase.

• 出版日期2018-1-16