Fig. 3.

Expression of ms-npf is regulated by fru. (A and B) Normal expression of ms-npf in dsx mutants. (A) Three NPF-immunoreactive D1-neurons in a dsx-null mutant. (B) npf transcripts in three L1-s and one D2 neurons in an XY dsx¹ fly. (C) Lack of NPF-immunoreactive D1-neurons in a fru-null mutant male. (D) Lack of npf transcripts in L1-s and D2 neurons of a fru⁴ homozygous male. (E–G) Colocalization of FRU^M in ms-npf neurons. GFP-labeled ms-npf neurons (green) are shown (Left), FRU^M-immunoreactivity (red) (Center), and a merger of the two signals (Right). FRU^M immunoreactivity is seen in the nuclei of D1 (E), D2 (F), and L1-s (G) neurons but not in sex-nonspecific L1-l neurons. [Scale bars, 100 μm (A–D) and 25 μm (E–G).]