proteinlipid

Proteinlipid refers to the interactions and associations between proteins and lipids in biological systems. It encompasses non-covalent protein-lipid interactions that recruit proteins to membranes or lipid domains, and covalent lipid modifications that anchor proteins to membranes. Studied across cell biology and biochemistry, proteinlipid phenomena underlie membrane structure, signaling, trafficking, and lipid transport.

Non-covalent interactions include peripheral membrane proteins that bind to lipid head groups via electrostatics, and proteins with hydrophobic or amphipathic regions that insert shallowly into the membrane. Lipid composition and membrane curvature influence binding, orientation, and activity of proteins.

Covalent lipidation attaches lipid moieties to specific amino acid residues, enabling stable membrane association or cycling between compartments. Common forms include N-myristoylation, S-palmitoylation, and prenylation (farnesylation or geranylgeranylation). GPI anchors tether proteins to the outer leaflet of membranes. Lipidation affects localization, stability, and protein interactions.

Lipoproteins are multi-component protein-lipid particles that transport cholesterol and triglycerides in the bloodstream. They consist of lipids organized in cores or surfaces with specialized apolipoproteins that stabilize and direct lipoprotein metabolism. LDL, HDL, and VLDL illustrate how protein and lipid components cooperate in lipid transport and signaling.

Researchers study proteinlipid interactions with mass spectrometry, lipidomics, fluorescence assays, and structural methods such as cryo-electron microscopy. Understanding these interactions is important for health and disease, including membrane disorders, metabolic syndrome, and cancer.