Related Experiment Video
Updated: Jul 21, 2026

Protocols for Analyzing the Role of Paneth Cells in Regenerating the Murine Intestine using Conditional Cre-lox Mouse Models
Published on: November 21, 2015
p27(Kip1) is an inducer of intestinal epithelial cell differentiation
1Section of Physiology, Cornell University, Ithaca, New York 14853, USA. aq10@cornell.edu
Abstract:
Constant renewal of the intestinal epithelium is a highly coordinated process that has been subject to intense investigation, but its regulatory mechanisms are still essentially unknown. In this study, we have demonstrated that forced expression of the cyclin-dependent kinase inhibitors (CKIs) p27(Kip1) and p21(Cip1/WAF1) in human intestinal epithelial cells led to expression of differentiation markers at both the mRNA and protein levels. Cell differentiation was temporally dissociated from inhibition of retinoblastoma protein phosphorylation and growth arrest, already established 1 day after infection with recombinant adenoviruses. p27(Kip1) proved significantly more efficient than p21(Cip1/WAF1) in induction of cell differentiation. In contrast, forced expression of p16(INK4a) resulted in growth arrest without induction of differentiation markers. These results implicate both p27(Kip1) and p21(Cip1/WAF1) in the differentiation-timing process, but p21(Cip1/WAF1) may act indirectly by increasing p27(Kip1) levels. These results also suggest that induction of intestinal epithelial cell differentiation by CKIs is not related to their effects on the cell cycle and may involve interactions with cellular components other than cyclins and cyclin-dependent kinases.
Related Concept Videos
Inhibition of Cdk Activity
Abnormal Proliferation
Renewal of Intestinal Stem Cells
Role of Ephrin-Eph Signalling in Intestinal Stem Cell Renewal
Somatic to iPS Cell Reprogramming
Role Of Notch Signalling In Intestinal Stem Cell Renewal
Direct cell-to-cell contact is needed for the activation of Notch signaling. The signal is initiated when a notch ligand binds to a receptor on an adjacent cell, also...

