Extended Data Fig. 4: Uncoupling between the gRNA cascade and the reporter cascade.

a, Top, diagram demonstrating the predicted correct order for conditional reporter and gRNA activation. Bottom, representative example of the correct order for a cascade of gRNAs controlling the activation of multiple reports in trans. Since gRNA#1 is active from the beginning and gRNA#2 requires activation by gRNA#1, the activation of the RFP reporter should precede the activation of the GFP. N=10 brains. b, Example where the activation of the second reporter occurs before the first reporter. In both cases the example corresponds to the lateral lineage in the AL, although this was also observed in other lineages. Green, red and gray, immunohistochemistry for GFP, RFP and nc82 (counterstaining) respectively. In the schemes, circled numbers represent the order of events occurring in the cascade. Scale bar = 15 μm. n=10 brains.