The telo-box, an interstitial telomere motif, was shown to regulate gene expression in root meristems, in synergy with a cis-acting element involved in the activation of expression of plant eEF1A genes, encoding the translation elongation factor EF1A, and of several ribosomal protein genes. We demonstrate here that the telo-box is also required for transcription activation by two other cis elements present within the promoter of genes encoding the acidic ribosomal protein rp40 and the proliferating cell nuclear antigen respectively. The control of gene expression by telo-boxes during cell cycle progression in Arabidopsis root meristems is discussed. A parallel is drawn with the function of telomeric sequences in Saccharomyces cerevisiae.
