• Here, we highlight that an important RNA sequence region, encompassing an exon-intron hairpin loop (also called IDX-rasISS1), of the H-Ras pre-mRNA may encode an ncRNA that regulates p68 RNA helicase. (lidsen.com)
  • Endocytic trafficking dynamically regulates neuronal plasma membrane protein presentation and activity, and plays a central role in excitability and plasticity. (umassmed.edu)
  • With the exception of the relatively well-known KRAS, HRAS and NRAS proteins, little is known about how the interactions of the other RAS human paralogs affect cancer evolution and response to treatment. (oncotarget.com)
  • RAS proteins are the founding members of the RAS superfamily of GTPases. (oncotarget.com)
  • [3] HRas is a small G protein in the Ras subfamily of the Ras superfamily of small GTPases . (wikidoc.org)
  • The RAS protein family is a set of small GTPases that function as binary switches by alternating their activation state from GTP-bound (active) to GDP-bound (inactive). (oncotarget.com)
  • The Ras family of GTPases is a collection of molecular switches that link receptors on the plasma membrane to signaling pathways that regulate cell proliferation and differentiation. (embl.de)
  • The rate of conversion is usually slow but can be sped up dramatically by an accessory protein of the GTPase activating protein (GAP) class, for example RasGAP . (wikidoc.org)
  • A mouse homologue of the Drosophila tumor suppressor l(2)tid gene defines a novel Ras GTPase-activating protein (RasGAP)-binding protein. (embl.de)
  • Once bound to Guanosine triphosphate , H-Ras will activate a Raf kinase like c-Raf , the next step in the MAPK/ERK pathway . (wikidoc.org)
  • HRAS acts as a molecular on/off switch, once it is turned on it recruits and activates proteins necessary for the propagation of the receptor's signal, such as c-Raf and PI 3-kinase . (wikidoc.org)
  • It is known that the human Ras GTPase activating protein (GAP) p120-GAP can be phosphorylated by different members of the Src kinase family and recently phosphorylation of the GDP/GTP exchange factor (GEF) CDC25Mm/GRF1 by proteins of the Src kinase family has been revealed in vivo [Kiyono, M., Kaziro, Y. & Satoh, T. (2000) J. Biol. (embl.de)
  • In addition to its association with Ras, GAP has been shown to bind to several tyrosine-phosphorylated proteins in cells stimulated by growth factors or expressing transforming tyrosine kinase variants. (embl.de)
  • GTPase HRas also known as transforming protein p21 is an enzyme that in humans is encoded by the HRAS gene . (wikidoc.org)
  • The HRAS protein is a GTPase and is an early player in many signal transduction pathways and is usually associated with cell membranes due to the presence of an isoprenyl group on its C-terminus . (wikidoc.org)
  • In turn HRAS can bind to proteins of the Guanine Nucleotide Exchange Factor (GEF) class, for example SOS1 , which forces the release of bound nucleotide. (wikidoc.org)
  • Each of these mutations changes an amino acid in a critical region of the HRAS protein. (wikidoc.org)
  • The mutations responsible for Costello syndrome lead to the production of an HRAS protein that is permanently active. (wikidoc.org)
  • HRAS has been shown to be a proto-oncogene . (wikidoc.org)
  • this mutation substitutes one protein building block (amino acid) for another amino acid in the HRAS protein. (wikidoc.org)
  • The altered HRAS protein is permanently activated within the cell. (wikidoc.org)
  • These mutations lead to an HRAS protein that is always active and can direct cells to grow and divide without control. (wikidoc.org)
  • In higher eukaryotes these proteins are involved in signal transduction pathways controlling a diverse array of essential cellular functions, such as growth, differentiation and survival [ 1 ]. (oncotarget.com)
  • Mutants of Ras are found in 25-30% of human tumors. (embl.de)
  • However, with the exception of a few well-studied protein models, the precise functions of the thirty-five human RAS paralogs and their relation in terms of sequence conservation, gene expression and protein-protein interactions remain poorly understood [ 2 ]. (oncotarget.com)
  • Here we report the cloning and characterization of a novel GAP-binding protein, mTid-1, a DnaJ chaperone protein that represents the murine homolog of the Drosophila tumor suppressor l(2)tid gene. (embl.de)
  • We found specific conserved amino acid positions in this group that map to the binding sites of RAS with many of their signaling effectors, suggesting that these pairs could share interacting partners. (oncotarget.com)
  • All known oncogenic mutants of Ras map to a small subset of amino acids. (embl.de)
  • In the human genome, the RAS family includes a large number of related genes (paralogs). (oncotarget.com)
  • Our results show that many RAS proteins with divergent sequences are found close together in the human interactome. (oncotarget.com)
  • This study broadens our understanding of the human RAS signaling network and stresses the importance of considering its potential cross-talk in future therapies. (oncotarget.com)
  • p120 GTPase-activating protein (GAP) down-regulates Ras by stimulating GTP hydrolysis of active Ras. (embl.de)
  • These results underscore the potential relevance of cross-talking in the RAS signaling network, which should be taken into account when considering the inhibitory activity of drugs targeting specific RAS oncoproteins. (oncotarget.com)
  • When mutated, proto-oncogenes have the potential to cause normal cells to become cancerous . (wikidoc.org)
  • In this study we performed a comprehensive analysis of the relationship between the phylogeny of RAS proteins and their location in the protein interaction network. (oncotarget.com)
  • Despite its obvious importance for carcinogenesis, the role of Gln-61 in the GAP-stimulated GTPase activity of Ras has remained a mystery. (embl.de)
  • As it still remains unclear how these phosphorylations can influence the Ras pathway we have analyzed the ability of p60c-Src and Lck to phosphorylate these two Ras regulators and have compared the activity of the phosphorylated and unphosphorylated forms. (embl.de)
  • The phosphorylation of p120-GAP by p60c-Src inhibited its ability to stimulate the Ha-Ras-GTPase activity, whereas phosphorylation by Lck did not display any effect. (embl.de)
  • Our results suggest that phosphorylation by p60c-Src and Lck is a selective process that can modulate the activity of p120-GAP and CDC25Mm towards Ras proteins. (embl.de)
  • Instead of triggering cell growth in response to particular signals from outside the cell, the overactive protein directs cells to grow and divide constantly. (wikidoc.org)