Schematic representation of the promoter:reporter gene constructs and GUS activity in different plant tissues. The uceA1.7 and uceApro2 constructs were sub-cloned and compared to the commonly used CaMV35Sd plant promoter. GUS specific activity was measured by a fluorometric assay in A. thaliana leaves, stems, floral buds and roots. CaMV35Sd: modified viral constitutive promoter; AMV: viral 5'UTR enhancer; uidA//tNOS: GUS gene with the NOS terminator; uceA1.7: GhGDRP85 regulatory sequence containing uceApro2, and the 5'UTR of GhGDRP8; uceApro2: GhGDRP85 gene promoter. The figure elements are not to scale.