Abstract
The bz locus in maize, which directs synthesis of the enzyme UDPglucose:flavonoid glucosyltransferase (UFGT) in the endosperm, is 1 of many loci at which controlling element-induced phenotypic changes are known. To characterize the nature of such modifications, several bz mutants derived by transposition of the controlling element Ds to the Bz gene were analyzed. Three mutants lacked UFGT at all stages of endosperm development. Two others apparently made an altered UFGT, and in 1 of these, the enzyme showed an altered developmental profile.