Leukocyte receptor tyrosine kinase

Leukocyte receptor tyrosine kinase
Identifiers
Symbols	LTK; TYK1
External IDs	OMIM: 151520 MGI: 96840 HomoloGene: 130502 ChEMBL: 5627 GeneCards: LTK Gene
EC number	2.7.10.1
Gene Ontology Molecular function • protein kinase activity • protein tyrosine kinase activity • transmembrane receptor protein tyrosine kinase activity • ATP binding Cellular component • plasma membrane • integral to plasma membrane • membrane Biological process • protein phosphorylation • apoptotic process • signal transduction • transmembrane receptor protein tyrosine kinase signaling pathway • cell proliferation • positive regulation of neuron projection development • phosphatidylinositol 3-kinase cascade • cellular response to retinoic acid Sources: Amigo / QuickGO
RNA expression pattern
More reference expression data
Orthologs
Species	Human	Mouse
Entrez	4058	17005
Ensembl	ENSG00000062524	ENSMUSG00000027297
UniProt	P29376	P08923
RefSeq (mRNA)	NM_001135685	NM_008523
RefSeq (protein)	NP_001129157	NP_032549
Location (UCSC)	Chr 15: 41.8 – 41.81 Mb	Chr 2: 119.75 – 119.76 Mb
PubMed search	[1]	[2]

Leukocyte receptor tyrosine kinase is an enzyme that in humans is encoded by the LTK gene.

The protein encoded by this gene is a member of the ALK/LTK receptor family of receptor tyrosine kinases (RTKs) whose ligand is unknown. Closely related to the insulin receptor family of RTKs. Tyrosine-specific phosphorylation of proteins is a key to the control of diverse pathways leading to cell growth and differentiation. Two alternatively spliced transcript variants encoding different isoforms have been described for this gene.

Interactions

LTK has been shown to interact with IRS-1, Shc, and PIK3R1.

Further reading

• Krolewski JJ, Dalla-Favera R (1991). "The ltk gene encodes a novel receptor-type protein tyrosine kinase.". Embo J. 10 (10): 2911–9. PMID 1655406. 
• Krolewski JJ, Lee R, Eddy R, et al. (1990). "Identification and chromosomal mapping of new human tyrosine kinase genes.". Oncogene 5 (3): 277–82. PMID 2156206. 
• Ben-Neriah Y, Bauskin AR (1988). "Leukocytes express a novel gene encoding a putative transmembrane protein-kinase devoid of an extracellular domain.". Nature 333 (6174): 672–6. doi:10.1038/333672a0. PMID 2836739. 
• Toyoshima H, Kozutsumi H, Maru Y, et al. (1993). "Differently spliced cDNAs of human leukocyte tyrosine kinase receptor tyrosine kinase predict receptor proteins with and without a tyrosine kinase domain and a soluble receptor protein.". Proc. Natl. Acad. Sci. U.S.A. 90 (12): 5404–8. doi:10.1073/pnas.90.12.5404. PMID 7685902. 
• Richard I, Broux O, Chiannilkulchai N, et al. (1995). "Regional localization of human chromosome 15 loci.". Genomics 23 (3): 619–27. doi:10.1006/geno.1994.1550. PMID 7851890. 
• Kozutsumi H, Toyoshima H, Hagiwara K, et al. (1994). "Human ltk receptor tyrosine kinase binds to PLC-gamma 1, PI3-K, GAP and Raf-1 in vivo.". Oncogene 9 (10): 2991–8. PMID 8084603. 
• Kozutsumi H, Toyoshima H, Hagiwara K, et al. (1993). "Identification of the human ltk gene product in placenta and hematopoietic cell lines.". Biochem. Biophys. Res. Commun. 190 (2): 674–9. doi:10.1006/bbrc.1993.1101. PMID 8427607. 
• Ueno H, Sasaki K, Kozutsumi H, et al. (1996). "Growth and survival signals transmitted via two distinct NPXY motifs within leukocyte tyrosine kinase, an insulin receptor-related tyrosine kinase.". J. Biol. Chem. 271 (44): 27707–14. doi:10.1074/jbc.271.44.27707. PMID 8910363. 
• Snijders AJ, Ho SC, Haase VH, et al. (1997). "A lymphocyte-specific Ltk tyrosine kinase isoform is retained in the endoplasmic reticulum in association with calnexin.". J. Biol. Chem. 272 (2): 1297–301. doi:10.1074/jbc.272.2.1297. PMID 8995435. 
• Ueno H, Honda H, Nakamoto T, et al. (1997). "The phosphatidylinositol 3' kinase pathway is required for the survival signal of leukocyte tyrosine kinase.". Oncogene 14 (25): 3067–72. doi:10.1038/sj.onc.1201153. PMID 9223670. 
• Espanel X, Huguenin-Reggiani M, Van Huijsduijnen RH (2003). "The SPOT technique as a tool for studying protein tyrosine phosphatase substrate specificities.". Protein Sci. 11 (10): 2326–34. doi:10.1110/ps.0213402. PMID 12237455. 
• Strausberg RL, Feingold EA, Grouse LH, et al. (2003). "Generation and initial analysis of more than 15,000 full-length human and mouse cDNA sequences.". Proc. Natl. Acad. Sci. U.S.A. 99 (26): 16899–903. doi:10.1073/pnas.242603899. PMC 139241. PMID 12477932. 
• Li N, Nakamura K, Jiang Y, et al. (2004). "Gain-of-function polymorphism in mouse and human Ltk: implications for the pathogenesis of systemic lupus erythematosus.". Hum. Mol. Genet. 13 (2): 171–9. doi:10.1093/hmg/ddh020. PMID 14695357.