Abstract
The vascular system plays an important role in nutrient and signal transportation in land plants. Xylogen has been isolated and identified from zinnia tracheary element (TE) differentiation culture system as a factor directing continuous formation of xylem strands. Xylogen is an arabinogalactan protein (AGP) with non-specific lipid transfer protein (nsLTP) domain and glycosylated phosphatidylinositol (GPI) anchor domain. Homology search has revealed genes sequentially homologous to xylogen in Arabidopsis genome. These xylogen homologs have well conserved nsLTP domain and diverged AGP domain. In order to study their histological expression pattern, we have produced some transgenic lines harboring xylogen homologous gene promoter::GUS constructs. Histochemical localization of these reporter gene showed distinctive temporal and spatial expression patterns, indicating that the xylogen homologs may be functionally diversed in plant development.
