Abstract
RGS family members are GTPase activating proteins (GAPs) that antagonize signaling by heterotrimeric G proteins. Injection of Xenopus embryos with RNA encoding rat RGS4 (rRGS4), a GAP for G(i) and G(q), resulted in shortened trunks and decreased skeletal muscle. This phenotype is nearly identical to the effect of injection of either frzb or dominant negative Xwnt-8. Injection of human RGS2, which selectively deactivates G(q), had similar effects. rRGS4 inhibited the ability of early Xwnt-8 but not Xdsh misexpression to cause axis duplication. This effect is distinct from axin family members that contain RGS-like domains but act downstream of Xdsh. We identified two Xenopus RGS4 homologs, one of which, Xrgs4a, was expressed as a Spemann organizer component. Injection of Xenopus embryos with Xrgs4a also resulted in shortened trunks and decreased skeletal muscle. These results suggest that RGS proteins modulate Xwnt-8 signaling by attenuating the function of a G protein.
Publication types
-
Research Support, Non-U.S. Gov't
MeSH terms
-
Adaptor Proteins, Signal Transducing
-
Amino Acid Sequence
-
Animals
-
Cloning, Molecular
-
Dishevelled Proteins
-
Embryo, Nonmammalian / metabolism
-
GTP-Binding Proteins / metabolism
-
Genes, Dominant
-
Glycoproteins*
-
Humans
-
Immunohistochemistry
-
In Situ Hybridization
-
Intracellular Signaling Peptides and Proteins
-
Mice
-
Microinjections
-
Molecular Sequence Data
-
Muscle, Skeletal / embryology
-
Muscle, Skeletal / metabolism
-
Phenotype
-
Phosphoproteins / metabolism
-
Plasmids
-
Protein Binding
-
Proteins / metabolism
-
Proto-Oncogene Proteins / antagonists & inhibitors*
-
Proto-Oncogene Proteins / metabolism*
-
RGS Proteins / biosynthesis*
-
RGS Proteins / genetics
-
RGS Proteins / metabolism
-
RGS Proteins / physiology*
-
Rats
-
Reverse Transcriptase Polymerase Chain Reaction
-
Sequence Homology, Amino Acid
-
Signal Transduction*
-
Time Factors
-
Wnt Proteins
-
Xenopus / embryology*
-
Xenopus Proteins
-
Zebrafish Proteins*
Substances
-
Adaptor Proteins, Signal Transducing
-
DVL1 protein, Xenopus
-
Dishevelled Proteins
-
Glycoproteins
-
Intracellular Signaling Peptides and Proteins
-
Phosphoproteins
-
Proteins
-
Proto-Oncogene Proteins
-
RGS Proteins
-
Rgs2 protein, mouse
-
WD repeat containing planar cell polarity effector
-
Wnt Proteins
-
Xenopus Proteins
-
Zebrafish Proteins
-
wnt8a protein, Xenopus
-
RGS4 protein
-
GTP-Binding Proteins