Two FRT sites have been inserted into the endogenous Pkc98E locus (the first in an intron, the second in a non-coding exon), such that they flank the sequence that encodes the Pkc98E kinase domain. A DsRed marker has also been inserted (in a non-coding exon), downstream of the second FRT site. This results in a conditional allele in which the kinase domain can be excised by using FLP recombinase.