Bigger Is not Better

Science's STKE  11 Dec 2001:
Vol. 2001, Issue 112, pp. tw458
DOI: 10.1126/stke.2001.112.tw458

The tumor suppressor gene Pten also plays a critical role for normal brain development. Standard Pten deletion mutants in mice are lethal in early development, so Groszer et al. (see the Perspective by Penninger and Woodgett) developed a conditional knockout that deletes PTEN in the central nervous system at mid-gestation. These mice showed hyperactivation of certain signal transduction pathways; they also exhibited enlarged brains with multiple malformations, and more and bigger neural cells. Analysis of cell proliferation and apoptosis in the mutant brains suggests that PTEN controls progression of neural progenitor cells through the cell cycle.

M. Groszer, R. Erickson, D. D. Scripture-Adams, R. Lesche, A. Trumpp, J. A. Zack, H. I. Kornblum, X. Liu, H. Wu, Negative regulation of neural stem/progenitor cell proliferation by the Pten tumor suppressor gene in vivo. Science 294, 2186-2189 (2001). [Online Journal]

J. M. Penninger, J. Woodgett, Stem cells: PTEN-coupling tumor suppression to stem cells? Science 294, 2116-2118 (2001). [Online Journal]