SOS1

Son of sevenless homolog 1 (Drosophila)
250px PDB rendering based on 1awe.
Available structures PDB Ortholog search: PDBe, RCSB List of PDB id codes 1AWE, 1BKD, 1DBH, 1NVU, 1NVV, 1NVW, 1NVX, 1Q9C, 1XD2, 1XD4, 1XDV, 2II0, 3KSY, 4NYI, 4NYJ, 4NYM, 4URU, 4URV, 4URW, 4URX, 4URY, 4URZ, 4US0, 4US1, 4US2
Identifiers
Symbols	SOS1 ; GF1; GGF1; GINGF; HGF; NS4
External IDs	OMIM: 182530 MGI: 98354 HomoloGene: 4117 GeneCards: SOS1 Gene
Gene ontology Molecular function • DNA binding • Ras guanyl-nucleotide exchange factor activity • Rho guanyl-nucleotide exchange factor activity • GTPase activator activity • protein binding • SH3 domain binding • protein heterodimerization activity Cellular component • cytosol • plasma membrane • postsynaptic density • neuronal cell body Biological process • B cell homeostasis • signal transduction • epidermal growth factor receptor signaling pathway • small GTPase mediated signal transduction • Ras protein signal transduction • axon guidance • blood coagulation • insulin receptor signaling pathway • fibroblast growth factor receptor signaling pathway • platelet activation • regulation of T cell differentiation in thymus • regulation of Rho protein signal transduction • Fc-epsilon receptor signaling pathway • regulation of T cell proliferation • positive regulation of apoptotic process • positive regulation of GTPase activity • innate immune response • positive regulation of epidermal growth factor receptor signaling pathway • neurotrophin TRK receptor signaling pathway • leukocyte migration • regulation of small GTPase mediated signal transduction • positive regulation of small GTPase mediated signal transduction • apoptotic signaling pathway • regulation of pro-B cell differentiation Sources: Amigo / QuickGO
RNA expression pattern
File:PBB GE SOS1 212777 at tn.png
File:PBB GE SOS1 212780 at tn.png
More reference expression data
Orthologs
Species	Human	Mouse
Entrez	6654	20662
Ensembl	ENSG00000115904	ENSMUSG00000024241
UniProt	Q07889	Q62245
RefSeq (mRNA)	NM_005633	NM_009231
RefSeq (protein)	NP_005624	NP_033257
Location (UCSC)	Chr 2: 38.98 – 39.12 Mb	Chr 17: 80.39 – 80.48 Mb
PubMed search	[1]	[2]

Son of sevenless homolog 1 is a protein that in humans is encoded by the SOS1 gene.

Function

RAS genes (e.g., MIM 190020) encode membrane-bound guanine nucleotide-binding proteins that function in the transduction of signals that control cell growth and differentiation. Binding of GTP activates RAS proteins, and subsequent hydrolysis of the bound GTP to GDP and phosphate inactivates signaling by these proteins. GTP binding can be catalyzed by guanine nucleotide exchange factors for RAS, and GTP hydrolysis can be accelerated by GTPase-activating proteins (GAPs). The first exchange factor to be identified for RAS was the S. cerevisiae CDC25 gene product. Genetic analysis indicated that CDC25 is essential for activation of RAS proteins. In Drosophila, the protein encoded by the 'son of sevenless' gene (Sos) contains a domain that shows sequence similarity with the catalytic domain of CDC25. Sos may act as a positive regulator of RAS by promoting guanine nucleotide exchange.[supplied by OMIM]

Clinical significance

Recent studies also show that mutations in Sos1 can cause Noonan syndrome and hereditary gingival fibromatosis type 1. Noonan syndrome has also been shown to be caused by mutations in KRAS and PTPN11 genes. activators of the MAP kinase pathway.

Interactions

SOS1 has been shown to interact with:

• ABI1,
• BCR gene,
• CRK,
• EPS8,
• Epidermal growth factor receptor,
• FRS2,
• Grb2,
• HRAS,
• ITSN1,
• MUC1,
• NCK1,
• PLCG1,
• PTPN11,
• SH3KBP1, and
• SHC1. and

See also

• Son of Sevenless

External links

• GeneReviews/NCBI/NIH/UW entry on Noonan syndrome
• http://www.noonansyndrome.org
• http://ghr.nlm.nih.gov/gene=sos1

This article incorporates text from the United States National Library of Medicine, which is in the public domain.