Ric 8A


Gene Symbol: Ric 8A
Description: RIC8 guanine nucleotide exchange factor A
Alias: Ric-8A, Ric8, synembryn-A, heterotrimeric G protein guanine nucleotide exchange factor Ric-8A, resistance to inhibitors of cholinesterase 8 homolog, resistance to inhibitors of cholinesterase 8A, resistance to inhibitors of cholinesterase 8A-like protein, synembryn
Species: rat
Products:     Ric 8A

Top Publications

  1. Tall G, Krumins A, Gilman A. Mammalian Ric-8A (synembryn) is a heterotrimeric Galpha protein guanine nucleotide exchange factor. J Biol Chem. 2003;278:8356-62 pubmed
    ..mammalian homologs of the Caenorhabditis elegans protein Ric-8 were identified in these screens: Ric-8A (Ric-8/synembryn) and Ric-8B...
  2. Thomas C, Tall G, Adhikari A, Sprang S. Ric-8A catalyzes guanine nucleotide exchange on G alphai1 bound to the GPR/GoLoco exchange inhibitor AGS3. J Biol Chem. 2008;283:23150-60 pubmed publisher
    ..Galpha(i1) complex, even when present at very high concentrations. The action of Ric-8A on AGS3:Galpha(i1).GDP ensures unidirectional activation of Galpha subunits that cannot be reversed by AGS3. ..
  3. Vellano C, Shu F, Ramineni S, Yates C, Tall G, Hepler J. Activation of the regulator of G protein signaling 14-G?i1-GDP signaling complex is regulated by resistance to inhibitors of cholinesterase-8A. Biochemistry. 2011;50:752-62 pubmed publisher
    ..These findings demonstrate that RGS14 is a newly appreciated integrator of unconventional Ric-8A and G?i1 signaling. ..
  4. Kant R, Zeng B, Thomas C, Bothner B, Sprang S. Ric-8A, a G protein chaperone with nucleotide exchange activity induces long-range secondary structure changes in G?. elife. 2016;5: pubmed publisher
    ..In contrast to GPCRs, Ric-8A interacts with Switches I and II of G? and possibly at the G? domain interface. These extensive interactions provide both allosteric and direct catalysis of GDP unbinding and release and GTP binding. ..
  5. Tõnissoo T, Koks S, Meier R, Raud S, Plaas M, Vasar E, et al. Heterozygous mice with Ric-8 mutation exhibit impaired spatial memory and decreased anxiety. Behav Brain Res. 2006;167:42-8 pubmed
    ..Therefore, described alterations seem to be specific for anxiety and spatial learning. Based on these results we can conclude the importance of ric-8 in the regulation of memory and emotional behavior. ..
  6. Tall G, Gilman A. Resistance to inhibitors of cholinesterase 8A catalyzes release of Galphai-GTP and nuclear mitotic apparatus protein (NuMA) from NuMA/LGN/Galphai-GDP complexes. Proc Natl Acad Sci U S A. 2005;102:16584-9 pubmed
  7. Wang S, Lai H, Chiu Y, Ou R, Huang C, Chern Y. Regulation of type V adenylate cyclase by Ric8a, a guanine nucleotide exchange factor. Biochem J. 2007;406:383-8 pubmed
  8. Tõnissoo T, Lulla S, Meier R, Saare M, Ruisu K, Pooga M, et al. Nucleotide exchange factor RIC-8 is indispensable in mammalian early development. Dev Dyn. 2010;239:3404-15 pubmed publisher
    ..Furthermore, the orientation of the Ric-8(-/-) embryo in the uterus was abnormal. Our study reveals that the activity of RIC-8 protein is irreplaceable for the correct gastrulation of mouse embryo. ..
  9. Thomas C, Briknarová K, Hilmer J, Movahed N, Bothner B, Sumida J, et al. The nucleotide exchange factor Ric-8A is a chaperone for the conformationally dynamic nucleotide-free state of G?i1. PLoS ONE. 2011;6:e23197 pubmed publisher

More Information


  1. Vellano C, Maher E, Hepler J, Blumer J. G protein-coupled receptors and resistance to inhibitors of cholinesterase-8A (Ric-8A) both regulate the regulator of g protein signaling 14 RGS14·G?i1 complex in live cells. J Biol Chem. 2011;286:38659-69 pubmed publisher
    ..Together, these findings indicate that RGS14 can form complexes with GPCRs in cells that are dependent on G?(i/o) and that these RGS14·G?(i1)·GPCR complexes may be substrates for other signaling partners such as Ric-8A. ..
  2. Black L, Thomas C, Nix G, Terwilliger M, Sprang S, Ross J. Nanosecond Dynamics of G?i1 Bound to Nucleotides or Ric-8A, a G? Chaperone with GEF Activity. Biophys J. 2016;111:722-731 pubmed publisher
    ..Induction of G?i1 structural heterogeneity by Ric-8A provides a mechanism for nucleotide release. ..