Background

Published studies indicate that intestinal tumors are initiated from intestinal epithelial stem cells.

Since mutant K-Ras strongly promotes tumor initiation and progression in the intestine, we would like to know whether mutant K-Ras also affects the proliferative kinetics of intestinal stem cells

Approach

• Some stem cell populations are defined by their quiescence in adult tissues. 

• These populations are identified via their ability to retain label over long periods of time.

• Our system for labeling stem cells in the adult small intestinal epithelium utilizes a doxycycline-inducible form of Gfp-tagged histone H2B that is stably integrated into chromatin.

• H2B-Gfp is diluted by half each time a cell divides, therefore quiescent cells retain the H2B-Gfp label.