Previous Article | Next Article 
Molecular and Cellular Biology, June 2006, p. 4511-4518, Vol. 26, No. 12
0270-7306/06/$08.00+0 doi:10.1128/MCB.00238-06
Copyright © 2006, American Society for Microbiology. All Rights Reserved.
Essential Role of Pten in Body Size Determination and Pancreatic ß-Cell Homeostasis In Vivo
Kinh-Tung T. Nguyen,1
Panteha Tajmir,1
Chia Hung Lin,1
Nicole Liadis,1
Xu-Dong Zhu,1
Mohammed Eweida,1
Gunce Tolasa-Karaman,2
Fang Cai,2
Rennian Wang,3
Tadahiro Kitamura,4
Denise D. Belsham,2
Michael B. Wheeler,2
Akira Suzuki,5
Tak W. Mak,1,6 and
Minna Woo1,7*
Department of Medicine, Medical Biophysics, Institute of Medical Science, Ontario Cancer Institute, University of Toronto, Toronto, Ontario, Canada,1
Department of Physiology, University of Toronto, Toronto, Ontario, Canada,2
Department of Physiology and Pharmacology, University of Western Ontario, London, Ontario, Canada,3
Department of Medicine, Columbia University, New York, New York,4
Department of Molecular Biology, Akita University School of Medicine, Akita, Japan,5
The Advanced Medical Discovery Institute and The Campbell Family Institute for Breast Cancer Research, Toronto, Ontario, Canada,6
Department of Medicine, St. Michael's Hospital, Toronto, Ontario, Canada7
Received 8 February 2006/
Returned for modification 21 March 2006/
Accepted 30 March 2006
PTEN (phosphatase with tensin homology) is a potent negative regulator of phosphoinositide 3-kinase (PI3K)/Akt signaling, an evolutionarily conserved pathway that signals downstream of growth factors, including insulin and insulin-like growth factor 1. In lower organisms, this pathway participates in fuel metabolism and body size regulation and insulin-like proteins are produced primarily by neuronal structures, whereas in mammals, the major source of insulin is the pancreatic ß cells. Recently, rodent insulin transcription was also shown in the brain, particularly the hypothalamus. The specific regulatory elements of the PI3K pathway in these insulin-expressing tissues that contribute to growth and metabolism in higher organisms are unknown. Here, we report PTEN as a critical determinant of body size and glucose metabolism when targeting is driven by the rat insulin promoter in mice. The partial deletion of PTEN in the hypothalamus resulted in significant whole-body growth restriction and increased insulin sensitivity. Efficient PTEN deletion in ß cells led to increased islet mass without compromise of ß-cell function. Parallel enhancement in PI3K signaling was found in PTEN-deficient hypothalamus and ß cells. Together, we have shown that PTEN in insulin-transcribing cells may play an integrative role in regulating growth and metabolism in vivo.
* Corresponding author. Mailing address: Princess Margaret Hospital, 8th Floor, Room 8-113, Toronto, Ontario, Canada M5G 2M9. Phone: (416) 946-4501, ext. 3971. Fax: (416) 946-2086. E-mail:
mwoo{at}uhnres.utoronto.ca.
Molecular and Cellular Biology, June 2006, p. 4511-4518, Vol. 26, No. 12
0270-7306/06/$08.00+0 doi:10.1128/MCB.00238-06
Copyright © 2006, American Society for Microbiology. All Rights Reserved.
This article has been cited by other articles:
-
Mori, H., Inoki, K., Opland, D., Munzberg, H., Villanueva, E. C., Faouzi, M., Ikenoue, T., Kwiatkowski, D. J., MacDougald, O. A., Myers, M. G. Jr., Guan, K.-L.
(2009). Critical roles for the TSC-mTOR pathway in {beta}-cell function. Am. J. Physiol. Endocrinol. Metab.
297: E1013-E1022
[Abstract]
[Full Text]
-
Pigeau, G. M., Kolic, J., Ball, B. J., Hoppa, M. B., Wang, Y. W., Ruckle, T., Woo, M., Manning Fox, J. E., MacDonald, P. E.
(2009). Insulin Granule Recruitment and Exocytosis Is Dependent on p110{gamma} in Insulinoma and Human {beta}-Cells. Diabetes
58: 2084-2092
[Abstract]
[Full Text]
-
Harb, G., Vasavada, R. C., Cobrinik, D., Stewart, A. F.
(2009). The Retinoblastoma Protein and Its Homolog p130 Regulate the G1/S Transition in Pancreatic {beta}-Cells. Diabetes
58: 1852-1862
[Abstract]
[Full Text]
-
Haskell-Luevano, C., Schaub, J. W., Andreasen, A., Haskell, K. R., Moore, M. C., Koerper, L. M., Rouzaud, F., Baker, H. V., Millard, W. J., Walter, G., Litherland, S. A., Xiang, Z.
(2009). Voluntary exercise prevents the obese and diabetic metabolic syndrome of the melanocortin-4 receptor knockout mouse. FASEB J.
23: 642-655
[Abstract]
[Full Text]
-
Radziszewska, A., Choi, D., Nguyen, K.-T. T., Schroer, S. A., Tajmir, P., Wang, L., Suzuki, A., Mak, T. W., Evan, G. I., Woo, M.
(2009). PTEN Deletion and Concomitant c-Myc Activation Do Not Lead to Tumor Formation in Pancreatic {beta} Cells. J. Biol. Chem.
284: 2917-2922
[Abstract]
[Full Text]
-
Mito, T., Noji, S.
(2008). The Two-Spotted Cricket Gryllus bimaculatus: An Emerging Model for Developmental and Regeneration Studies. CSH Protocols
2008: pdb.emo110-pdb.emo110
[Abstract]
[Full Text]
-
Choi, D., Nguyen, K.-T. T., Wang, L., Schroer, S. A., Suzuki, A., Mak, T. W., Woo, M.
(2008). Partial Deletion of Pten in the Hypothalamus Leads to Growth Defects that Cannot be Rescued by Exogenous Growth Hormone. Endocrinology
149: 4382-4386
[Abstract]
[Full Text]
-
Wagner, M., Koschnick, S., Beilke, S., Frey, M., Adler, G., Schmid, R. M.
(2008). Selective expansion of the {beta}-cell compartment in the pancreas of keratinocyte growth factor transgenic mice. Am. J. Physiol. Gastrointest. Liver Physiol.
294: G1139-G1147
[Abstract]
[Full Text]
-
Hu, Z., Lee, I. H., Wang, X., Sheng, H., Zhang, L., Du, J., Mitch, W. E.
(2007). PTEN Expression Contributes to the Regulation of Muscle Protein Degradation in Diabetes. Diabetes
56: 2449-2456
[Abstract]
[Full Text]