Homologs of eukaryotic Ras superfamily proteins in prokaryotes and their novel phylogenetic correlation with their eukaryotic analogs

The Fcγ receptor is a cell surface protein essential in the immune response that binds IgG-opsonized particles resulting in phagocytosis. Phagocytosis is a process used to remove pathogens and confine them in a vacuole that will enable their breakdown. The members of the Ras superfamily of small G proteins have been identified in samples where the activated Fcγ receptor complex was captured and analyzed using tandem mass spectrometry. The protein Rap. beloning to the Ras superfamily, guanosine triphosphatases (GTPase) activating proteins (GAPs), which promote the dissociation of GTP, and guanine nucleotide exchange factors (GEFs), that permits the exchange of GDP for GTP, were detected by SEQUEST in RAW 264.7 macrophages and futher analyzed using various methods. In this study, Raps, RasGAPs, and RapGEFs, were observed by tandem mass spectrometry and sequence correlation analysis. The selected isoforms were confirmed by Western blots, live cell confocal microscopy with fluorescent fusion constructs and antibody staining to verify the localization of Ras proetins, specifically Rap1, p120RasGAP and C3G, a RapGEF, to activated Fc reeceptor [sic].

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Inhibitors of the Ras superfamily G-proteins, Part B

10.1016/c2012-0-03661-7 ◽

2013 ◽

Keyword(s):

G Proteins ◽

Ras Superfamily

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Inhibitors of the Ras Superfamily G-proteins, Part A

10.1016/c2012-0-03660-5 ◽

2013 ◽

Keyword(s):

G Proteins ◽

Ras Superfamily

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Ras Superfamily of Small GTP Binding Proteins

10.1007/springerreference_36546 ◽

2011 ◽

Keyword(s):

Binding Proteins ◽

Gtp Binding Proteins ◽

Gtp Binding ◽

Ras Superfamily

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p190RhoGAPs, the ARHGAP35- and ARHGAP5-Encoded Proteins, in Health and Disease

Cells ◽

10.3390/cells8040351 ◽

2019 ◽

Vol 8 (4) ◽

pp. 351 ◽

Cited By ~ 5

Author(s):

Héraud ◽

Pinault ◽

Lagrée ◽

Moreau

Keyword(s):

Rho Gtpases ◽

Large Family ◽

Negative Regulator ◽

Nucleotide Exchange ◽

Cellular Mechanisms ◽

Guanine Nucleotide Exchange ◽

Nucleotide Exchange Factors ◽

Physiological Processes ◽

Ras Superfamily ◽

Spatio Temporal

Small guanosine triphosphatases (GTPases) gathered in the Rat sarcoma (Ras) superfamily represent a large family of proteins involved in several key cellular mechanisms. Within the Ras superfamily, the Ras homolog (Rho) family is specialized in the regulation of actin cytoskeleton-based mechanisms. These proteins switch between an active and an inactive state, resulting in subsequent inhibiting or activating downstream signals, leading finally to regulation of actin-based processes. The On/Off status of Rho GTPases implicates two subsets of regulators: GEFs (guanine nucleotide exchange factors), which favor the active GTP (guanosine triphosphate) status of the GTPase and GAPs (GTPase activating proteins), which inhibit the GTPase by enhancing the GTP hydrolysis. In humans, the 20 identified Rho GTPases are regulated by over 70 GAP proteins suggesting a complex, but well-defined, spatio-temporal implication of these GAPs. Among the quite large number of RhoGAPs, we focus on p190RhoGAP, which is known as the main negative regulator of RhoA, but not exclusively. Two isoforms, p190A and p190B, are encoded by ARHGAP35 and ARHGAP5 genes, respectively. We describe here the function of each of these isoforms in physiological processes and sum up findings on their role in pathological conditions such as neurological disorders and cancers.

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