regulator of G-protein signaling 20; Gz-selective GTPase-activating protein; G(z)GAP; Gz-GAP; regulator of G-protein signaling Z1; regulator of Gz-selective protein signaling 1 (RGS20, RGSZ1, ZGAP1)

Function

• inhibits signal transduction by increasing GTPase activity of G-alpha subunits increasing the amount of inactive GDP-bound form
• binds selectively to Gz-alpha & Gi-alpha-2 subunits, accelerates their GTPase activity & regulates their signaling activities
• the Gz-alpha activity is inhibited by the phosphorylation & palmitoylation of the G-protein
• negatively regulates mu-opioid receptor-mediated activation of G-proteins (putative)
  • fatty acylated
• heavily palmitoylated in the cysteine string motif (putative)
• N- & O-glycosylated in synapsomal membranes
• Ser phosphorylated in synapsomal membranes
• sumoylated by SUMO1 & SUM02 in synaptosomes
• the sumoylated forms act as a scaffold for sequestering mu-opioid receptor-activated G-alpha subunits (putative)
• forms a complex with Gz-alpha/Gi-alpha-2 subunits & mu-opioid receptors; formation of this complex results in mu-opioid receptor desensitization
• interacts with OPRM1 (putative)

Structure

contains 1 RGS domain

Compartment

• membrane, lipid-anchor
• nucleus, cytoplasm
• shuttles between the cytoplasm/cell membrane & the nucleus (putative)
• anchored to the membrane through palmitoylation

Alternative splicing

named isoforms=6

Expression

• isoform 5 is expressed in brain, & at high levels in the caudate nucleus & temporal lobe

More general terms

• regulator of G-protein signaling

Database

• Entrez gene: http://www.ncbi.nlm.nih.gov/sites/entrez?db=gene&cmd=Retrieve&dopt=Graphics&list_uids=8601
• Kegg: http://www.genome.jp/dbget-bin/www_bget?hsa:8601
• OMIM: https://mirror.omim.org/entry/607193
• UniProt: http://www.uniprot.org/uniprot/O76081.html