Inx2 protein distribution in dominant Inx2UA104 mutant gut cells.
The image shows cells of the posterior embryonic gut of an 8-10 hour old embryo of genotype Inx2UA104 / Y. Inx2 protein (green) is detected using anti-Inx2 rabbit polyclonal primary antibody and an FITC-conjugated anti-rabbit secondary. The protein is distributed around the cell membrane and does not aggregate into the brightly fluorescent plaques observed in wild type animals. The Inx2UA104 point mutation alters an amino acid located only two amino acid positions away from that altered by the Inx2TA181 mutation. Both substitutions occur in the second extracellular domain on either side of a highly conserved proline residue. This domain therefore has a crucial role in determining the correct subcellular distribution of Inx2 and consequently the activity of gap junctions that contain innexin subunits that interact with Inx2, such as Inx3. Some bright punctae can be detected (arrow). These could be transport vesicles or some perduring maternally-contributed wild type Inx2 protein.