Abstract
In higher plants, somatic embryogenesis is thought to a direct evidence of 'totipotency', but little is known about the mechanism of acquisition of embryogenic competence in somatic cells. In carrot, somatic embryos can be induced by the stress treatment. In this system, expression of many embryo-specific genes were found during the stress treatment without any morphological change. It was expected to identify the genes involving in the acquisition of embryogenic competence by expression analysis during the stress treatment. From the analyses using Arabidopsis microarray, there were some up-regulated genes by the stress treatment. One of these up-regulated genes was No Apical Meristem-like 1 (NAM-like 1) and expressed in floral tissue and calli, but not in somatic embryos. Overexpressors of this gene formed numerous shoots on the basal part of inflorescence as compared to wild type. These results indicate that NAM-like 1 gene might involve in stimulation of organogenesis.
