Adulthood-only expression of putNIG.7904R under the combined control of Scer\GAL4esg.PU and Gal80[ts] (induced by temperature shift from 18[o]C to 29[o]C) leads to increased numbers of presumptive intestinal progenitors/enteroblasts and enteroblasts (i.e. esg- and GBE+Su(H)-positive cells, respectively), as well as increased mitotic index (pH3-positive cells), in the adult posterior midgut, as compared to controls; the size of the polyploid cells expressing putNIG.7904R is smaller than fully differentiated enterocytes, indicating a defect in maturation.