(A–E) Villus epithelial cells lack differentiated features characteristic of enterocytes (Alkaline phosphatase activity, B), but do not exhibit appreciable differences in goblet (PAS, C), enteroendocrine (CHGA, D), or Paneth (LYZ1, E) cell lineages. (F) These findings are corroborated by qRT-PCR analysis of markers of differentiated intestinal cell lineages, with markers of the enterocyte lineage particularly affected by TFAM loss, relative to proliferative cell markers or markers of other differentiated cell lineages. (t-test, n=7 controls, 4 mutants). All histology is imaged from the duodenum. Scale bars = 50µm.