UASt regulatory sequences drive expression of mutant (contains the R196C mutation) Hsap\WDR5 cDNA (NCBI BC001635.1), tagged at the C-terminal with 3xTag:HA. The ORF is flanked by a pair of incompatible FRT sites (FRT5 and FRT2), which allows for future in vivo exchange of either the promoter or tag sequence. A loxP site is present upstream of UASt.