Arrestins are a small family of proteins important for regulating signal transduction at G protein-coupled receptors. Arrestins were first discovered as a part of a conserved two-step mechanism for regulating the activity of G protein-coupled receptors (GPCRs) in the visual rhodopsin system. In response to a stimulus, GPCRs activate heterotrimeric G proteins. In order to turn off this response, or adapt to a persistent stimulus, active receptors need to be desensitized. The first step in desensitization is phosphorylation of the receptor by a class of serine/threonine kinases called G protein coupled receptor kinases (GRKs). GRK phosphorylation specifically prepares the activated receptor for arrestin binding. Arrestin binding to the receptor blocks further G protein-mediated signaling and targets receptors for internalization, and redirects signaling to alternative G protein-independent pathways. Here you can see different representations of the structure of bovine arrestin, determined by X-ray crystallography to 2.4 A resolution (PDB code: 7JXA)
#molecularart ... #immolecular ... #arrestin ... #signalling ... #gprotein ... #receptor ... #xray
Rendered with @proteinimaging and finished with @corelphotopaint
#molecularart ... #immolecular ... #arrestin ... #signalling ... #gprotein ... #receptor ... #xray
Rendered with @proteinimaging and finished with @corelphotopaint
