Current Protein and Peptide Science - Volume 12, Issue 8, 2011

One third of the genome of any organism encodes intrinsic membrane proteins. Along with peripheral membrane proteins and proteins that only transiently interact with the membrane, these molecules are hard to study but of great importance to understand both the normal and pathological life of the cell. Biophysical methods are of the utmost importance when trying to unravel the molecular details of processes that have b Read More

Proto-oncoproteins are a heterogeneous group of proteins that induce cellular differentiation, proliferation and growth, acting at different points of signaling cascades and in different cell compartments, through many different mechanisms. If the proto-oncogenes that give raise to proto-oncoproteins undergo genetic damage, they become oncogenes and their products are the oncoproteins responsible for cellular transfo Read More

The characterization of interactions between membrane proteins as they take place within the lipid bilayer poses a technical challenge, which is currently very difficult and, in many cases, impossible to overcome. The recent development of a method based in the combination two-color fluorescence cross-correlation spectroscopy with scanning of the focal volume allows the detection and quantification of interactions bet Read More

Single particle tracking (SPT) enables light microscopy at a sub-diffraction limited spatial resolution by a combination of imaging at low molecular labeling densities and computational image processing. SPT and related single molecule imaging techniques have found a rapidly expanded use within the life sciences. This expanded use is due to an increased demand and requisite for developing a comprehensive understanding Read More

Diffusing membrane constituents are constantly exposed to a variety of forces that influence their stochastic path. Single molecule experiments allow for resolving trajectories at extremely high spatial and temporal accuracy, thereby offering insights into en route interactions of the tracer. In this review we discuss approaches to derive information about the underlying processes, based on single molecule tracking experiments Read More

Flotillin-2 and flotillin-1, also called reggie-1 and reggie-2, are ubiquitously expressed and highly conserved proteins. Originally, they were described as neuronal regeneration proteins, but they appear to function in a wide variety of cellular processes, such as membrane receptor signaling, endocytosis, phagocytosis and cell adhesion. The molecular details of the function of flotillins in these processes have only been partially Read More

Tail-anchored proteins (TAPs) are a subclass of type II integral membrane proteins that carry out important and diverse functions within cells. Structurally, TAPs present an N-terminal domain exposed to the cytosol and a single transmembrane domain (TMD) close to the C-terminus, the latter is responsible for the targeting and insertion into the proper intracellular membrane (endoplasmic reticulum (ER), mitochondria, p Read More

Cell surface carbohydrates are important targets for many cell surface receptors, and they mediate crucial biological processes ranging from pathogen infectivity to neutrophil adhesion to drug targeting. A central challenge is to identify relationships between lectin architecture and function that influence the adhesion strength, avidity, and kinetics of receptor-glycan bonds. This information is central both to understa Read More

The influence of the lipid environment on the function of membrane proteins is increasingly recognized as crucial. Nevertheless, the molecular mechanisms underlying protein-lipid interactions remain obscure. Membrane lipid composition has a regulatory effect on membrane protein activity, and for a number of membrane proteins a clear correlation was found between protein activity and properties of the membran Read More