TRANSIENT EXPRESSION OF EXOGENOUS DNA IN INTACT, VIABLE WHEAT EMBRYOS FOLLOWING PARTICLE BOMBARDMENT

Expression of foreign DNA has been detected in intact, germinating wheat embryos (Triticum aestivum L.) following bombardment with tungsten particles complexed with a reporter gene encoding the bacterial enzyme β-glucuronidase ('GUS': E.C.3.2.1.31). Expression was detected in situ in individual cells and groups of cells, by supplying the germinating embryos with the chromogenic substrate of the GUS enzyme, 'X-gluc'. Expression was dependent on the presence of a constitutive plant promoter, the Cauliflower Mosaic Virus '35S' promoter, fused to the GUS structural coding sequence. The relative simplicity of this technique recommends its future use for the assay of regulatory elements which control the spatial and temporal specificity of genes expressed during embryo development. © 1990 Oxford University Press.