Wild-type His1 gene in the context of a histone gene repeat unit.
Wild-type His2A gene in the context of a histone gene repeat unit.
Wild-type His2B gene in the context of a histone gene repeat unit.
Wild-type His4 gene in the context of a histone gene repeat unit.
Each copy of His3 has been mutated to the His3.3 coding sequence by making 4 amino acid replacements.
Four copies of M{3xHisGU.H3.2-H3.3} rescue the formation of homozygous Df(2L)BSC104 clones in the wing disc. Homozygous Df(2L)BSC104 animals carrying four copies of M{3xHisGU.H3.2-H3.3} survive into the first instar larval stage with no obvious patterning defects.