An mRNA encoding a response regulator protein from Brassica napus is up-regulated during pod development

A novel cDNA (SAC29) was isolated by differential display from pod dehiscence zone tissue during a study directed at identifying genes expressed during pod development in oilseed rape (Brassica napus L.). SAC29 encodes a 136 amino acid putative peptide, which shows homology to various prokaryotic and eukaryotic response regulator proteins. The homologous regions are centred about the four highly conserved amino acid residues of bacterial receivers including the aspartic acid motif required for phosphorylation and subsequent transduction of the initial signal. Northern blot analysis of SAC29 showed hybridization to a 0.6 kb transcript which was most abundant in RNA extracted from the dehiscence zone of pods at 40 d after anthesis. The role of SAC29 as a component in a signalling cascade regulating dehiscence of the pod is discussed.