Fig. 3

Detection of reporter expression in an Arabidopsis line only transformed with E_rtip1 + 35Smini:GUS or :GFP. Plant expression vectors harboring respectively E_rtip1-, E_rtip1 + 35Smini-, E_rtip2-, E_rtip2 + 35Smini- and E_rtip3-fused GUS or GFP were constructed and their corresponding transgenic Arabidopsis (Col-0) lines were generated (till T2 or T3 generation, see “Methods” section). The enhancer/promoter activity was indicated by the GUS expression assayed via GUS-staining of transgenic plants grown on agar-plates (for 8 d) or pot-soil (over 2 months) (see “Methods” section). Except for the line transformed with E_rtip1 + 35Smini:GUS (termed here as P_{Ertip1+35Smini}:GUS), the GUS expression could not be detected in any tissue/organ of lines harboring respectively other individual constructs (data not shown). GUS-indicated enhancer/promoter activity was not detectable in flower organs and seeds of P_{Ertip1+35Smini}:GUS plants (data not shown). a The primary root (PR). b A mature zone of the PR. c The lateral root. d Plant upper parts (e.g. leave and hypocotyl). Green fluoresce observation of the PR tip of P_{Ertip1+35Smini}:GFP containing line (e) and J3411 (f). GUS, β-glucuronidase. A bar scale = 100 μm for a–f; the bar in 3 mm for d