Fig 5. C15 functions independently of aristaless.
(A) DNA-binding interaction between purified recombinant GST-C15HD and in vitro translated Al HD on Bar and bab2 enhancer sequences was examined in EMSA. In striking contrast to the BarEnh (compare lanes 2 and 3), upon addition of AlHD no heterodimeric C15-Al DNA complex (red asterisk in lane 3) could be detected with the CR1 probe (compare lanes 7 and 8). Note that adding control reticulocyte extracts led to the same diminished GST-C15HD binding to the CR1 probe. (B) Wild-type mid L3 leg disc expressing LAE-GFP. Merged GFP fluorescence (green) together with C15 (magenta) and Al (blue) immunostainings is shown, as well as each markers in isolation in (B’), (B”) and (B”‘), respectively. Note that isolated C15+ cells neither expressed LAE-RFP nor Al. (C-D) Mosaic Late L3 leg discs expressing the LAE-RFP reporter and harboring FO clones ectopically-expressing C15 either alone (C) or together with al dsRNA (D). Merged GFP fluorescence (green), RFP fluorescence (red) and Al immunostaining (cyan) are shown, as well as RFP and Al together, in (C”) and (D”), and both signals in isolation, in (C’) and (C”‘) and in (D’) and (D”‘), respectively. Despite Al depletion in a majority of C15-misexpressing FO cells, LAE-RFP expression remained fully down-regulated within all the cells of the examined clones (n = 8).