Diversity of Membrane Proteins

Membrane protein: is a protein molecule that is attached to, or associated with, the membrane of a cell

Membrane proteins have a diverse range of structures, functions and locations

There are two main types of proteins in the cell membrane:

  • Integral membrane proteins - embedded in the phospholipid bilayer (they go completely through the membrane layers)

  • Peripheral membrane proteins - indirectly or loosely attached to the surface of the cell membrane, but may dip slightly into the lipid bilayer

Examples of use

Description and examples

Cell adhesion

Cell adhesion molecules (CAM) involved in binding of cells with extracellular matrix

Enzymatic

Integral protein

Pumps for active transport

AKA transporters - actively move ions and /or solutes across membranes

Cell-to-cell communication

Protein-protein interactions (PPIs) - signalling

Channel or carrier proteins

Integral - form a pathway through which ions and molecules can move across a membrane

Hormone binding

G - protein - hormone binds to its membrane receptors