Figure 5. Ato⁺/Dac⁺ NBs divide symmetrically to produce two GMCs.

(A,B) First temporal window Dichaete⁺ and second temporal window Ato⁺ NBs localized Miranda (A) and Prospero (B) to the basal cortex during cell division. See also Figures S4 and S5.

(C) Quantification of the mean size of the two progeny of Dichaete⁺ and Ato⁺ NBs at the end of telophase. Dichaete⁺ NBs divided to self-renew (Bazooka, red) and produce a smaller GMC (Prospero, green)(see Movie 3). Ato⁺ NBs produced two progeny (Bazooka, red and Prospero, green) of the same size that both assumed a GMC fate (see Movie 4). Data are represented as a scattered plot ± SD. Unpaired two-tailed Student’s t test with Welch’s correction. Dichaete⁺ NBs progeny (t=10.79 df=7.338) and Ato⁺ NBs progeny (t=1.164 df=9.994), Asterisk indicates P value<0.0001.

(D) Division of an Ato⁺ NB produced a GMC (not shown in image) and a cell that expressed perduring Deadpan and nuclear Prospero (arrowheads; green), becoming the second GMC.

(E) A vertical system twin-spot MARCM clone of sister GMCs visualized with T4/T5-Gal4 showed two pairs of sibling T4/T5 neurons of opposite motion direction sensitivity, projecting to the same retinotopic position in the neuropile. Arrow points to layer a and arrowhead to layer b of the Lobula Plate (See also Figure S2).

(F) Schematic illustrating dIPC neurogenesis. Ato⁺ NBs divide to produce a GMC and a small cell that becomes a GMC.