Regulation of vascular development

The regulation of vascular development is one of the major unresolved issues of plant developmental biology. This overview provides a framework for the following four papers by describing key events of vascular development and highlighting recent advances in understanding their regulation. Vascular development includes: (1) formation of the longitudinal pattern of primary vascular strands (2) formation of the radial pattern of xylem and phloem within vascular strands (3) differentiation of specialized cell types from xylem and phloem precursors; and (4) cell proliferation and cell differentiation within the vascular cambium. Integration of information from diverse sub-disciplines, including comparative anatomy of primary vascular patterns, manipulative experiments testing the role of hormones in pattern formation and cell differentiation, analysis of mutual phenotypes, derailed characterization of cellular events, and use of molecular tools ro identify and determine gene function, will be essential fur further progress in understanding the regulation of these processes.