Expression of PR-5d and ERF Genes in Cultured Tobacco Cells and Their NaCl Stress-response

Abstract

The expression of pathogenesis-related protein-5d (PR-5d) and ethylene-responsive transcriptional factors (ERF1-4) for basic PR-proteins was measured in cultured tobacco cells. The PR-5d transcript markedly increased with culture, but only constant levels of transcripts of ERF1 (trans-activator) and ERF3 (repressor) were detected in cells. These different responses of PR-5d and ERF genes were also observed under NaCl stress; PR-5d transcript decreased and ERF levels were constant under NaCl stress. The effect of post-transcriptional regulation of ERF activity, especially ERF3, on the expression of basic PR genes including PR-5d is discussed.