Protein-coding gene in the species Homo sapiens
Guanine nucleotide-binding protein G(I)/G(S)/G(O) subunit gamma-T2 is a signalling protein protein that in humans and vertebrates is encoded by the GNGT2 gene.[5][6][7] Either GNGT1 or GNGT2 is the gamma subunit of the Gβγ part of transducin (written G(T) or Gt), a heterotrimeric G-protein naturally expressed in vertebrate retina rod and cone cell of the eye, where it is thought to play a crucial role in phototransduction. GNGT2 only occurs in cone cells, and GNGT1 only occurs in rod cells.
As the gamma subunit (Gγ) of three different families of G proteins (G(I)/Gi, G(S)/Gs and G(O)Go), GNGT2 is expressed in at least 23 tissues[8] and other cell types, including monocytes of the vertebrate innate immune system, where at increased levels it has been shown to be a potential prognostic marker for some types of cancer, including esophageal cancer.[9]
Several transcript variants encoding the GNGT2 protein have been found for the GNGT2 gene. There is evidence for use of multiple polyadenylation sites by this gene.[6]