Fig. 2.

Apoptosis in WT and PolgD257A small intestines. A: WT small intestine with apoptosis located at tip of each villus with large yellow arrows indicating apoptotic cells. Nuclei staining (DAPI), blue; terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL), green. B: PolgD257A small intestines have similar levels of apoptosis at the tip of each villus indicated with large yellow arrows. Small yellow arrows indicate an increase in apoptotic cells in the columnar epithelial cells along the length of the villi. An increase in apoptosis was found at the base of the villi in the crypts of Lieberkühn. C: quantification of apoptosis found in the columnar epithelial cells along the length of the villi. Number of mice is indicated within the bars. All data are represented as means ± SE. **P < 0.01, between WT (n = 11) and Polg (n = 8).