Insertion within Irk1.
Irk1NP2554 was detected in all 4 PDF+ small LNv neurons, in 2 to 3 of the 5 large LNv neurons but not in the fifth PDF-negative s-LNv neuron. Irk1NP2554 was detected in 1 of 6 dorsal lateral neurons (LNds) but not in dorsal clock neurons.