Fig. 1. GL3 and EGL3 promoter activity in the developing root. Expression of the GL3::GUS and EGL3::GUS reporter fusions in the root epidermis of 4-day-old seedlings. The magnified images (right) show the differential cell division rate of N- and H-cell files, indicating that both reporters are preferentially expressed in developing hair cells. The GL3::GUS reporter is also expressed in the quiescent center cells in the root meristem, but this does not seem to be associated with the role of GL3 in epidermal development (C.B. and J.S., unpublished).