This pathway was inferred from Homo sapiens pathway [http://www.wikipathways.org/index.php?title=Pathway:WP35&oldid=20751 WP35(r20751)] with a 94% conversion rate. G proteins, short for guanine nucleotide-binding proteins, are a family of proteins involved in second messenger cascades. G proteins are so called because they function as "molecular switches". They alternate from 'inactive' guanosine diphosphate (GDP) to 'active' guanosine triphosphate (GTP), which is a binding state, and which proceeds to regulate downstream cell processes. Source: [Wikipedia](https://en.wikipedia.org/wiki/G_protein) a71 d70 3103658 PubMed G proteins: a family of signal transducers. Annu Rev Cell Biol 1986 Stryer L Bourne HR 12040175 PubMed G protein pathways. Science 2002 Neves SR Ram PT Iyengar R G protein mediated signaling pathway PW:0000125 Pathway Ontology