Figure 3.

Co-expression of Nmr2 and Nmr1 in the Drosophila CNS.

Stage 13 (A,D,) stage 14 (B,E), and late stage 15 (C,F,G–I) wild-type embryos labeled for Nmr2 (A–C, G, I), Nmr1 (D–F, H, I) and co-labeled for Nmr1 and Nmr2 (I). (A) During stage 13 Nmr2 is expressed strongly in a cluster of medial neurons and weakly in a group of lateral neurons. (B) By stage 14, Nmr2 is expressed strongly in a cluster of approximately 10–15 cells per hemisegment with enhanced expression in the medial and intermediate regions of the nerve cord and diminished expression laterally. (C) This pattern of expression is prominently defined in stage 15 where Nmr2 is expressed strongly in a cluster of approximately 8 medial neurons (box) and 8 lateral neurons (bracket). Nmr2 is also expressed weakly in about 5–6 neurons within the lateral cluster (arrow). (D) During stage 13 Nmr1 is expressed strongly in a small number of medial neurons and expressed weakly in a few neurons in the intermediate region. (E) By stage 14, Nmr1 expression remains high in medial neurons and expression is now observed in additional neurons in the intermediate regions of the CNS. (F) By stage 15, Nmr1 is expressed in many discrete sets of neurons in the CNS: a medial cluster of approximately 3–5 neurons (box), a lateral cluster of 7–8 neurons (bracket), and a few dispersed lateral neurons (arrow). (G–I) Double-labeling for Nmr2 (green) and Nmr1 (red) in stage 15 embryos indicates that a subset of Nmr2-positive neurons express Nmr1 (merge).