Abstract
PSK is a secreted peptide originally found in plant cell culture. This peptide induces the plant cell proliferation and/or differentiation in vitro by means of specific receptors. As a first step of the functional analysis of PSK genes consists of five paralogs, we introduced PSK promotor::GUS constructs in Arabidopsis and analyzed their expression pattern. In Arabidopsis seedlings, GUS expression was observed mainly at vascular bundle in the leaves and stele in roots. PSK should have some functions in these region. We also analyzed their expression pattern in excised leaf disk.. GUS expression was detected around the wound region after 12 h of leaf excision. In the presence of auxin and cytokinin, callus formation was observed only in the GUS positive region, indicating the involvement of PSK in cellular dedifferentiation and restructure of tissue as a wound response.
