This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Right arrow Citation Map
Services
Right arrow E-mail this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrowReprints and Permissions
Right arrow Copyright Information
Right arrow Books from ASM Press
Right arrow MicrobeWorld
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Haegebarth, A.
Right arrow Articles by Tyner, A. L.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Haegebarth, A.
Right arrow Articles by Tyner, A. L.

 Previous Article  |  Next Article 

Molecular and Cellular Biology, July 2006, p. 4949-4957, Vol. 26, No. 13
0270-7306/06/$08.00+0     doi:10.1128/MCB.01901-05
Copyright © 2006, American Society for Microbiology. All Rights Reserved.

Protein Tyrosine Kinase 6 Negatively Regulates Growth and Promotes Enterocyte Differentiation in the Small Intestine

Andrea Haegebarth,1 Wenjun Bie,1 Ruyan Yang,1 Susan E. Crawford,2 Valeri Vasioukhin,3 Elaine Fuchs,4 and Angela L. Tyner1*

Departments of Biochemistry and Molecular Genetics and Medicine, University of Illinois at Chicago, Chicago, Illinois 60607,1 Department of Pathology, Northwestern University, Chicago, Illinois 60611,2 Division of Human Biology, Fred Hutchinson Cancer Research Center, Seattle, Washington 98109,3 Howard Hughes Medical Institute, The Rockefeller University, New York, New York 100214

Received 28 September 2005/ Returned for modification 7 February 2006/ Accepted 8 April 2006

Protein tyrosine kinase 6 (PTK6) (also called Brk or Sik) is an intracellular tyrosine kinase that is expressed in breast cancer and normal epithelial linings. In adult mice, PTK6 expression is high in villus epithelial cells of the small intestine. To explore functions of PTK6, we disrupted the mouse Ptk6 gene. We detected longer villi, an expanded zone of PCNA expression, and increased bromodeoxyuridine incorporation in the PTK6-deficient small intestine. Although differentiation of major epithelial cell types occurred, there was a marked delay in expression of intestinal fatty acid binding protein, suggesting a role for PTK6 in enterocyte differentiation. However, fat absorption was comparable in wild-type and Ptk6–/– mice. It was previously shown that the serine threonine kinase Akt is a substrate of PTK6 and that PTK6-mediated phosphorylation of Akt on tyrosine resulted in inhibition of Akt activity. Consistent with these findings, we detected increased Akt activity and nuclear ß-catenin in intestines of PTK6-deficient mice and decreased nuclear localization of the Akt substrate FoxO1 in villus epithelial cells. PTK6 contributes to maintenance of tissue homeostasis through negative regulation of Akt in the small intestine and is associated with cell cycle exit and differentiation in normal intestinal epithelial cells.


* Corresponding author. Mailing address: University of Illinois College of Medicine, Department of Biochemistry and Molecular Genetics, M/C 669, 900 S. Ashland Ave., Chicago, IL 60607. Phone: (312) 996-7964. Fax: (312) 413-0353. E-mail: atyner{at}uic.edu.


Molecular and Cellular Biology, July 2006, p. 4949-4957, Vol. 26, No. 13
0270-7306/06/$08.00+0     doi:10.1128/MCB.01901-05
Copyright © 2006, American Society for Microbiology. All Rights Reserved.




This article has been cited by other articles:

  • Palka-Hamblin, H. L., Gierut, J. J., Bie, W., Brauer, P. M., Zheng, Y., Asara, J. M., Tyner, A. L. (2010). Identification of {beta}-catenin as a target of the intracellular tyrosine kinase PTK6. J. Cell Sci. 123: 236-245 [Abstract] [Full Text]  
  • Guo, J., Longshore, S., Nair, R., Warner, B. W. (2009). Retinoblastoma Protein (pRb), but Not p107 or p130, Is Required for Maintenance of Enterocyte Quiescence and Differentiation in Small Intestine. J. Biol. Chem. 284: 134-140 [Abstract] [Full Text]  
  • Wang, M.-L., Keilbaugh, S. A., Cash-Mason, T., He, X. C., Li, L., Wu, G. D. (2008). Immune-mediated signaling in intestinal goblet cells via PI3-kinase- and AKT-dependent pathways. Am. J. Physiol. Gastrointest. Liver Physiol. 295: G1122-G1130 [Abstract] [Full Text]  
  • D'Aniello, S., Irimia, M., Maeso, I., Pascual-Anaya, J., Jimenez-Delgado, S., Bertrand, S., Garcia-Fernandez, J. (2008). Gene Expansion and Retention Leads to a Diverse Tyrosine Kinase Superfamily in Amphioxus. Mol Biol Evol 25: 1841-1854 [Abstract] [Full Text]  
  • Simmen, F. A., Xiao, R., Velarde, M. C., Nicholson, R. D., Bowman, M. T., Fujii-Kuriyama, Y., Oh, S. P., Simmen, R. C. M. (2007). Dysregulation of intestinal crypt cell proliferation and villus cell migration in mice lacking Kruppel-like factor 9. Am. J. Physiol. Gastrointest. Liver Physiol. 292: G1757-G1769 [Abstract] [Full Text]  
  • Ostrander, J. H., Daniel, A. R., Lofgren, K., Kleer, C. G., Lange, C. A. (2007). Breast Tumor Kinase (Protein Tyrosine Kinase 6) Regulates Heregulin-Induced Activation of ERK5 and p38 MAP Kinases in Breast Cancer Cells. Cancer Res. 67: 4199-4209 [Abstract] [Full Text]