PTK7

Protein tyrosine kinase 7 (inactive)
Identifiers
Symbols	PTK7 ; CCK-4; CCK4
External IDs	OMIM: 601890 MGI: 1918711 HomoloGene: 43672 GeneCards: PTK7 Gene
EC number	2.7.10.1
Gene ontology Molecular function • protein tyrosine kinase activity • protein binding • ATP binding Cellular component • integral component of plasma membrane • cell-cell junction • focal adhesion Biological process • establishment of planar polarity • axis elongation • cell adhesion • signal transduction • positive regulation of neuron projection development • cell migration • peptidyl-tyrosine phosphorylation • actin cytoskeleton reorganization • wound healing • establishment of epithelial cell apical/basal polarity • convergent extension • canonical Wnt signaling pathway • lung-associated mesenchyme development • cellular response to retinoic acid • cochlea morphogenesis • planar cell polarity pathway involved in neural tube closure Sources: Amigo / QuickGO
RNA expression pattern
More reference expression data
Orthologs
Species	Human	Mouse
Entrez	5754	71461
Ensembl	ENSG00000112655	ENSMUSG00000023972
UniProt	Q13308	Q8BKG3
RefSeq (mRNA)	NM_001270398	NM_175168
RefSeq (protein)	NP_001257327	NP_780377
Location (UCSC)	Chr 6: 43.08 – 43.16 Mb	Chr 17: 46.56 – 46.63 Mb
PubMed search

Tyrosine-protein kinase-like 7 also known as colon carcinoma kinase 4 (CCK4) is a receptor tyrosine kinase that in humans is encoded by the PTK7 gene.^[1][2]

Function

Receptor protein tyrosine kinases transduce extracellular signals across the cell membrane. A subgroup of these kinases lack detectable catalytic tyrosine kinase activity but retain roles in signal transduction. The protein encoded by this gene an intracellular domain with tyrosine kinase homology and may function as a cell adhesion molecule. This gene is thought to be expressed in colon carcinomas but not in normal colon, and therefore may be a marker for or may be involved in tumor progression. Four transcript variants encoding four different isoforms have been found for this gene.^[2]

PTK7 serves as a context-dependent signalling switch for the Wnt pathways (particularly in planar cell polarity related functions such as convergent extension and neural crest cell migration) and appears to have similar functions for plexin and Flt-1 pathways.^[3]

References

1. Mossie K, Jallal B, Alves F, Sures I, Plowman GD, Ullrich A (Nov 1995). "Colon carcinoma kinase-4 defines a new subclass of the receptor tyrosine kinase family". Oncogene 11 (10): 2179–84. PMID 7478540.
2. "Entrez Gene: PTK7 PTK7 protein tyrosine kinase 7".
3. Peradziryi H, Tolwinski NS, Borchers A (Aug 2012). "The many roles of PTK7: a versatile regulator of cell-cell communication". Archives of Biochemistry and Biophysics 524 (1): 71–6. doi:10.1016/j.abb.2011.12.019. PMID 22230326.

Further reading

• Lee ST, Strunk KM, Spritz RA (Dec 1993). "A survey of protein tyrosine kinase mRNAs expressed in normal human melanocytes". Oncogene 8 (12): 3403–10. PMID 8247543.
• Park SK, Lee HS, Lee ST (Feb 1996). "Characterization of the human full-length PTK7 cDNA encoding a receptor protein tyrosine kinase-like molecule closely related to chick KLG". Journal of Biochemistry 119 (2): 235–9. doi:10.1093/oxfordjournals.jbchem.a021228. PMID 8882711.
• Banga SS, Ozer HL, Park SK, Lee ST (1997). "Assignment of PTK7 encoding a receptor protein tyrosine kinase-like molecule to human chromosome 6p21.1-->p12.2 by fluorescence in situ hybridization". Cytogenetics and Cell Genetics 76 (1-2): 43–4. doi:10.1159/000134511. PMID 9154124.
• Jung JW, Ji AR, Lee J, Kim UJ, Lee ST (Dec 2002). "Organization of the human PTK7 gene encoding a receptor protein tyrosine kinase-like molecule and alternative splicing of its mRNA". Biochimica et Biophysica Acta 1579 (2-3): 153–63. doi:10.1016/s0167-4781(02)00536-5. PMID 12427550.
• Zhang H, Li XJ, Martin DB, Aebersold R (Jun 2003). "Identification and quantification of N-linked glycoproteins using hydrazide chemistry, stable isotope labeling and mass spectrometry". Nature Biotechnology 21 (6): 660–6. doi:10.1038/nbt827. PMID 12754519.
• Kobus FJ, Fleming KG (Feb 2005). "The GxxxG-containing transmembrane domain of the CCK4 oncogene does not encode preferential self-interactions". Biochemistry 44 (5): 1464–70. doi:10.1021/bi048076l. PMID 15683231.
• Katoh M, Katoh M (Sep 2007). "Comparative integromics on non-canonical WNT or planar cell polarity signaling molecules: transcriptional mechanism of PTK7 in colorectal cancer and that of SEMA6A in undifferentiated ES cells". International Journal of Molecular Medicine 20 (3): 405–9. doi:10.3892/ijmm.20.3.405. PMID 17671748.