Scaffold protein

A scaffold protein ( from the English " scaffold protein" ) is a specific protein whose main function is to provide protein complexes. Scaffold proteins usually have multiple protein domains that mediate binding to other proteins. The function of the protein complex can also be controlled by this scaffold proteins in which these interactions are controlled ( eg by means of phosphorylation).

Examples of scaffold proteins

The scaffold protein INAD in insect eyes

The protein INAD in the rhabdomeres of the fruit fly Drosophila melanogaster is a very well-studied scaffold protein, from which also a homologue in humans but has been found. It contains five PDZ domains, which specifically all proteins involved in signal transduction of visual spatial matching ( rhodopsin, kinases, ion channels ) and also anchored to the cytoskeleton (via a myosin ).

The protein titin in muscles of vertebrates

Titin is a very large protein in the muscle. The tasks of titin in the sarcomere are the ones who myosin filaments to center between the actin filaments and reset the contractile apparatus after stretching. Titin also serves as a scaffold protein for several other proteins ( calmodulin, actinin, etc.) that are essential for muscle work. It has this multiple SH3 domains, fibronectin type III domains and other domains.