tin45 mutants show a salivary gland phenotype. At stage 14, mutant salivary glands remain associated with the inner circular muscle layer, while in wild type, these structures become separate. After stage 15, cells from the distal tips of the tin45 salivary glands spread into the region of the undifferentiated midgut that forms the gastric caecae in wild-type embryos. The mutant glands become mispositioned and/or elongated and maintain contact with the area of the midgut immediately adjacent to the proventriculus.
In tin45/tin346 mutants the dorsal neurohemal organs (DNHs) are absent.
Some homozygous embryos hatch and survive as first instar larvae, even though they have midgut and body wall muscle defects. They fail to grow and show lethargic behavior and large midguts. The transverse nerve is missing, as are the dorsal neurohemal organs. Both the dorsal and ventral lateral bipolar dendrite neuron are disrupted when the transverse nerve is not formed. Segmental nerve b target muscles are abnormally innervated, and this is often associated with the loss of some muscle fibres. Transverse nerve exit glial cell cannot be found.
Strong mesodermal phenotype: midgut musculature is completely missing, midgut, foregut, proventriculus and hindgut appear normal. The pattern of body wall muscles is disrupted due to the absence of muscle founder cells. In the absence of visceral mesoderm the endoderm fails to migrate. The cardioblasts and pericardial cells are absent.