PTK6 explained

Tyrosine-protein kinase 6 is an enzyme that in humans is encoded by the PTK6 gene.^{[1] [2] [3]}

Function

Tyrosine-protein kinase 6—also known as BRK^[3] (breast tumor kinase)—is a cytoplasmic non-receptor protein kinase which may function as an intracellular signal transducer in epithelial tissues. The encoded protein has been shown to undergo autophosphorylation.

Clinical significance

Overexpression of this gene in mammary epithelial cells leads to sensitization of the cells to epidermal growth factor and results in a partially transformed phenotype. Expression of this gene has been detected at low levels in some breast tumors but not in normal breast tissue.^[3]

Interactions

PTK6 has been shown to interact with STAP2^[4] and KHDRBS1.^[5]

Further reading

• Serfas MS, Tyner AL . Brk, Srm, Frk, and Src42A form a distinct family of intracellular Src-like tyrosine kinases . Oncol. Res. . 13 . 6–10 . 409–19 . 2003 . 12725532 . 10.3727/096504003108748438.
• Mitchell PJ, Barker KT, Martindale JE, etal . Cloning and characterisation of cDNAs encoding a novel non-receptor tyrosine kinase, brk, expressed in human breast tumours . Oncogene . 9 . 8 . 2383–90 . 1994 . 8036022 .
• Kamalati T, Jolin HE, Mitchell PJ, etal . Brk, a breast tumor-derived non-receptor protein-tyrosine kinase, sensitizes mammary epithelial cells to epidermal growth factor . J. Biol. Chem. . 271 . 48 . 30956–63 . 1997 . 8940083 . 10.1074/jbc.271.48.30956 . free .
• Lee H, Kim M, Lee KH, etal . Exon-intron structure of the human PTK6 gene demonstrates that PTK6 constitutes a distinct family of non-receptor tyrosine kinase . Mol. Cells . 8 . 4 . 401–7 . 1998 . 10.1016/S1016-8478(23)13443-1 . 9749526 . free .
• Llor X, Serfas MS, Bie W, etal . BRK/Sik expression in the gastrointestinal tract and in colon tumors . Clin. Cancer Res. . 5 . 7 . 1767–77 . 1999 . 10430081 .
• Derry JJ, Richard S, Valderrama Carvajal H, etal . Sik (BRK) Phosphorylates Sam68 in the Nucleus and Negatively Regulates Its RNA Binding Ability . Mol. Cell. Biol. . 20 . 16 . 6114–26 . 2000 . 10913193 . 10.1128/MCB.20.16.6114-6126.2000 . 86087 .
• Mitchell PJ, Sara EA, Crompton MR . A novel adaptor-like protein which is a substrate for the non-receptor tyrosine kinase, BRK . Oncogene . 19 . 37 . 4273–82 . 2000 . 10980601 . 10.1038/sj.onc.1203775 . free .
• Kamalati T, Jolin HE, Fry MJ, Crompton MR . Expression of the BRK tyrosine kinase in mammary epithelial cells enhances the coupling of EGF signalling to PI 3-kinase and Akt, via erbB3 phosphorylation . Oncogene . 19 . 48 . 5471–6 . 2000 . 11114724 . 10.1038/sj.onc.1203931 . free .
• Hong E, Shin J, Bang E, etal . Complete sequence-specific 1H, 13C and 15N resonance assignments of the human PTK6 SH2 domain . J. Biomol. NMR . 19 . 3 . 291–2 . 2001 . 11330822 . 10.1023/A:1011221125013 . 20836477 .
• Deloukas P, Matthews LH, Ashurst J, etal . The DNA sequence and comparative analysis of human chromosome 20 . Nature . 414 . 6866 . 865–71 . 2002 . 11780052 . 10.1038/414865a . 2001Natur.414..865D . free .
• Kang KN, Kim M, Pae KM, Lee ST . Characterization of the 5'-flanking region of the human PTK6 gene . Biochim. Biophys. Acta . 1574 . 3 . 365–9 . 2002 . 11997104 . 10.1016/s0167-4781(02)00234-8.
• Qiu H, Miller WT . Regulation of the nonreceptor tyrosine kinase Brk by autophosphorylation and by autoinhibition . J. Biol. Chem. . 277 . 37 . 34634–41 . 2002 . 12121988 . 10.1074/jbc.M203877200 . free .
• Koo BK, Kim MH, Lee ST, Lee W . Purification and spectroscopic characterization of the human protein tyrosine kinase-6 SH3 domain . J. Biochem. Mol. Biol. . 35 . 3 . 343–7 . 2002 . 12297019 . 10.5483/BMBRep.2002.35.3.343 . free .
• Strausberg RL, Feingold EA, Grouse LH, etal . 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 . 2003 . 12477932 . 10.1073/pnas.242603899 . 139241 . 2002PNAS...9916899M . free .
• Coyle JH, Guzik BW, Bor YC, etal . Sam68 Enhances the Cytoplasmic Utilization of Intron-Containing RNA and Is Functionally Regulated by the Nuclear Kinase Sik/BRK . Mol. Cell. Biol. . 23 . 1 . 92–103 . 2003 . 12482964 . 10.1128/MCB.23.1.92-103.2003 . 140664 .
• Derry JJ, Prins GS, Ray V, Tyner AL . Altered localization and activity of the intracellular tyrosine kinase BRK/Sik in prostate tumor cells . Oncogene . 22 . 27 . 4212–20 . 2003 . 12833144 . 10.1038/sj.onc.1206465 . free .
• Qiu H, Miller WT . Role of the Brk SH3 domain in substrate recognition . Oncogene . 23 . 12 . 2216–23 . 2004 . 14676834 . 10.1038/sj.onc.1207339 . free .

Notes and References

1. Lee ST, Strunk KM, Spritz RA . A survey of protein tyrosine kinase mRNAs expressed in normal human melanocytes . Oncogene . 8 . 12 . 3403–10 . December 1993 . 8247543 .
2. Park SH, Lee KH, Kim H, Lee ST . Assignment of the human PTK6 gene encoding a non-receptor protein tyrosine kinase to 20q13.3 by fluorescence in situ hybridization . Cytogenet Cell Genet . 77 . 3–4 . 271–2 . September 1997 . 9284935 . 10.1159/000134595 .
3. Web site: PTK6 protein tyrosine kinase 6. National Center for Biotechnology Information (NCBI). 4 June 2020 .
4. Mitchell . P J . Sara E A . Crompton M R . August 2000 . A novel adaptor-like protein which is a substrate for the non-receptor tyrosine kinase, BRK . Oncogene . 19 . 37 . 4273–82 . ENGLAND. 0950-9232. 10980601 . 10.1038/sj.onc.1203775 . free .
5. Derry . J J . Richard S . Valderrama Carvajal H . Ye X . Vasioukhin V . Cochrane A W . Chen T . Tyner A L . August 2000 . Sik (BRK) Phosphorylates Sam68 in the Nucleus and Negatively Regulates Its RNA Binding Ability . Mol. Cell. Biol. . 20 . 16 . 6114–26 . UNITED STATES. 0270-7306. 10913193 . 10.1128/MCB.20.16.6114-6126.2000 . 86087 .