Expression of tnc^EY16369 under the control of either Scer\GAL4^byn-Gal4, Scer\GAL4^69B or Scer\GAL4^drm.7.1 results in an increase in the mean diameter of the large intestine lumen and an increase in the area of the small intestine lumen (resulting in a ballooned appearance).

Expression of tnc^EY16369 under the control of Scer\GAL4^en-e16E results in an increase in the mean diameter of the large intestine lumen, while the size of the small intestine lumen is unaffected. Both ventral and dorsal large intestine cells have enlarged apical cell circumferences. Local dilation of the salivary gland tube is seen, with all cells at the lumen perimeter showing enlarged apical cell circumferences (despite expression being limited to one a discrete cell cluster on one side of the tube at the site of the dilation).

Embryos expressing tnc^EY16369 under the control of Scer\GAL4^btl.PS have excessively dilated primary tracheal branches from stage 13 with enlarged apical cell circumferences. At stage 15, the dorsal trunks in have more cells at the lumen perimeter than normal, but the total number of tracheal cells is comparable to wild type.

Embryos expressing tnc^EY16369 under the control of Scer\GAL4^69B have dilated salivary glands, with the dilation becoming more apparent as development proceeds. This expansion is accompanied by enlarged apical cell circumferences and an increase in the number of cells encircling the lumen.

Expression of tnc^EY16369 under the control of Scer\GAL4^drm.7.1 results in dilation of the Malpighian tubule lumen.

No defects in the appearance of the developing epidermis or in epithelial cell shape are seen in embryos expressing tnc^EY16369 under the control of Scer\GAL4^en-e16E and examined between stages 13 and 16.

Expression of tnc^EY16369 under the control of Scer\GAL4^Act5C.PI results in 92% lethality. 66% of the adult escapers show wing defects which are characterised by a failure of wing expansion, and a large number of the adult escapers die within one or two days after eclosion. No male genitalia defects are seen.