Glycolipid transfer proteins (GLTPs) are small (24 kDa), soluble, ubiquitous proteins characterized by their ability to accelerate the intermembrane transfer of glycolipids in vitro. GLTP specificity encompasses both sphingoid- and glycerol-based glycolipids, but with a strict requirement that the initial sugar residue be beta-linked to the hydrophobic lipid backbone. The 3D architecture of GLTP reveals liganded structures with unique lipid-binding modes. The biochemical properties of GLTP action at the membrane surface have been studied rather comprehensively, but the biological role of GLTP remains enigmatic. What is clear is that GLTP differs distinctly from other known glycolipid-binding proteins, such as nonspecific lipid transfer proteins, lysosomal sphingolipid activator proteins, lectins, lung surfactant proteins as well as other lipid-binding/transfer proteins. Based on the unique conformational architecture that targets GLTP to membranes and enables glycolipid binding, GLTP is now considered the prototypical and founding member of a new protein superfamily in eukaryotes.
|Original language||English (US)|
|Number of pages||15|
|Journal||Biochimica et Biophysica Acta - Molecular and Cell Biology of Lipids|
|State||Published - Jun 2007|
Bibliographical noteFunding Information:
We wish to express our gratitude to former and present members of the REB and PM laboratories. Special thanks to Dinshaw J. Patel (Memorial Sloan Kettering Cancer Center) for the essential collaborative contributions enabling elucidation of GLTP structure as Co-PI of NIH/NCI CA121493, to Lucy Malinina for leading contributions in solving the structure of GLTP, and to Julian G. Molotkovsky (Shemyakin-Ovhininnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences) for synthesizing many of the sphingolipid fluorophores used to investigate GLTPs over the past decade. Financial support: REB, United States Public Health Service (NIH-GM45928 & NIH-CA121493) and the Hormel Foundation; PM, Academy of Finland, Sigrid Jusélius Foundation, Magnus Ehrnrooth Foundation, Svenska Kulturfonden, Medicinska Understödsföreningen Liv och Hälsa r.f., and Åbo Akademi University.
- Lipid transfer protein structure
- Membrane interaction motif