Research Paper|Volume 1, Issue 7|pp 637—651

The role of p38b MAPK in age-related modulation of intestinal stem cell proliferation and differentiation in Drosophila

Joung-Sun Park¹, Young-Shin Kim¹, Mi-Ae Yoo¹

¹Department of Molecular Biology, Pusan National University, Busan 609-735, Korea

Received: April 2, 2009Accepted: May 20, 2009Published: May 21, 2009

Copyright: © 2009 Park et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

Abstract

It is important to understand how age-related changes in intestinal stem cells (ISCs) may contribute to age-associated intestinal diseases, including cancer. Drosophila midgut is an excellent model system for the study of ISC proliferation and differentiation. Recently, age-related changes in the Drosophila midgut have been shown to include an increase in ISC proliferation and accumulation of mis-differentiated ISC daughter cells. Here, we show that the p38b MAPK pathway contributes to the age-related changes in ISC and progenitor cells in Drosophila. D-p38b MAPK is required for an age-related increase of ISC proliferation. In addition, this pathway is involved in age and oxidative stress-associated mis-differentiation of enterocytes and upregulation of Delta, a Notch receptor ligand. Furthermore, we also show that D-p38b acts downstream of PVF2/PVR signaling in these age-related changes. Taken together, our findings suggest that p38 MAPK plays a crucial role in the balance between ISC proliferation and proper differentiation in the adult Drosophila midgut.