Fig. 7.

Embryonic INP progeny contribute to the adult central complex. (A) The FLEXAMP memory cassette used for immortalization of embryonic INPs into the adult brain; modified from Bertet et al., 2014. (B-P) Central complex neuropil regions from flies containing FLEXAMP memory cassette reared at different temperature regimes to permanently label neurons born within all development (29°C positive control), no stage of development (18°C negative control) or specifically during late embryogenesis (29°C pulse) stained for GFP (green) and NC82 (magenta). (B-F) Positive controls reared at 29°C from embryo to adult with over 500 (n=4) of immortalized neurons innervating the protocerebral bridge (PB), the fan-shaped body (FB), the ellipsoid body (EB) and the noduli (NO). (G-K) Negative control adult brains of flies reared at 18°C from embryo to adult showing 10±5 (n=5) neurons from the adult 9D11-gal4 pattern innervating only the dorsal region of the FB. (L-R) Experimental adult brains from flies reared for 6 h pulse at 29°C at late embryonic stages, then reared at 18°C until adult (see Materials and Methods); there are 64±4 (n=12) neurons that innervate the PB, FB, EB but not the NO. (P′-R) Experimental adult brains with differences in innervation pattern within the EB (n=12). (P′) Single z plane from the anterior region shown in P with innervation of two wedges within the EB (yellow arrowheads) seen in 12/12 brains. (P″) Single z plane from posterior region shown in P showing widefield neuron innervation within the EB seen in 9/12 brains. (Q) EB with innervation of two wedges, lacking the widefield innervation (n=1). (R) EB with innervation of one wedge, lacking the widefield innervation (n=1). Yellow arrowheads in Q,R indicate wedge labeling in ellipsoid body. Scale bars: 20 μm. n>5 for positive control (29°C constitutive) and negative control (18°C constitutive); n>10 for experimental (29°C pulse).