We studied real-time interaction between poly(ethylene glycol)-conjugated phospholipids (PEG-lipids) and a supported lipid membrane by surface plasmon resonance (SPR) spectroscopy to understand dynamic behaviors of PEG-lipids on living cell membranes. Supported lipid membranes formed on a hydrophobic surface were employed as a model of living cell membrane. We prepared three kinds of PEG-lipids...

Extracellular Vesicles, including exosomes, are small membrane fragments released from many cell types, like Mesenchymal Stem Cells (MSCs). They were recognized as a mechanism of intercellular communication. They can transfer proteins, lipids and nucleic acids to other cells. Thus, they have many physiological (angiogenesis, coagulation and tissue repair, etc.) and pathological (e.g. in autoimm...

Recent studies of structure-function relationships in biological membranes have revealed fundamental concepts concerning the regulation of cellular membrane function by membrane lipids. Considerable progress has been made in understanding the roles played by two membrane lipids: cholesterol and phosphatidyl-ethanolamine. Cholesterol has been shown to regulate ion pumps, which in some cases show...

McDonald P, Veluthakal R, Kaur H, Kowluru A. Biologically active lipids promote trafficking and membrane association of Rac1 in insulin-secreting INS 832/13 cells. Am J Physiol Cell Physiol 292: C1216 –C1220, 2007. First published October 11, 2006; doi:10.1152/ajpcell.00467.2006.—Despite emerging evidence to suggest that glucose-stimulated insulin secretion (GSIS) requires membrane targeting of...

One of the most developed theories of phospholipid homeostasis is the intrinsic curvature hypothesis, which, in broad terms, postulates that cells regulate their lipid composition so as to keep constant the membrane stored curvature elastic energy. The implication of this hypothesis is that lipid composition is determined by a ratio control function consisting of the weighted sum of concentrati...

While membrane models now include the heterogeneous distribution of lipids, the impact of membrane charges on regulating the association of proteins with the plasma membrane is often overlooked. Charged lipids are asymmetrically distributed between the two leaflets of the plasma membrane, resulting in the inner leaflet being negatively charged and a surface potential that attracts and binds pos...

A wide range of signaling processes occurs at the cell surface through the reversible association of proteins from the cytosol to the plasma membrane. Some low abundant lipids are enriched at the membrane of specific compartments and thereby contribute to the identity of cell organelles by acting as biochemical landmarks. Lipids also influence membrane biophysical properties, which emerge as an...

Temperature exerts a first-order control on microbial populations, which constantly adjust the fluidity and permeability of their cell membrane lipids to minimize loss of energy by ion diffusion across the membrane. Analytical advances in liquid chromatography coupled to mass spectrometry have allowed the detection of a stunning diversity of bacterial and archaeal lipids in extreme environments...