Fig. 4. miR164-binding is required for CUC2 mRNA cleavage. (A) RT-PCR analysis of the CUC2s expression levels in STM::ALCR-alcA::erGFP alcA::CUC2-wt (left) and STM::ALCR-alcA::erGFP alcA::CUC2-m4 (right) transgenic lines. Ten-day-old seedlings were sampled after overnight ethanol induction of the CUC2-wt or CUC2-m4 gene. The primers used amplified RT products of the endogenous CUC2 gene and the CUC2-wt or CUC2-m4 transgenes. The same lines as in Fig. 3E were analysed and are plotted in the same order. (B) A cleavage product of CUC2 is detected in lines overexpressing CUC2 (2x35S::CUC2, arrow) and is absent in lines overexpressing the miR164-resistant CUC2-m4 (2x35S::CUC2-m4).