A 3200bp fragment of the endogenous pros locus (includes promoter, 5'UTR, start codons and a part of the first exon) has been replaced with a DNA cassette composed of 1. an attP site, 2. a loxP cassette that contains a Disc\RFP3xP3.cUa marker.
Larval prosKO MARCM clones are larger than control clones.