Cell cycle control and plant morphogenesis: is there an essential link?

Plant morphogenesis has some interesting features that may have consequence s for the regulation of cell division. In particular, the immobility of pla nt cells implies the necessity for highly accurate controls, in contrast wi th the flexibility of many developmental processes in animals. An important question in plant development concerns the status of the relationship betw een plant morphogenesis and cell division. In this review, we discuss the c urrent knowledge of the molecular mechanisms controlling the plant cell cyc le and how this could be differentially regulated during plant morphogenesi s. The plant genes involved are homologous to those of other higher eukaryo tes, suggesting a similar cell cycle machinery. A variety of mechanisms con trol these genes, reflecting the complexity of internal and environmental s ignals to which plants should respond. This intricate network requires an u pstream control mechanism to function as a failsafe system and to govern ce ll division and growth to produce the correct plant shape. (C) 1999 John Wi ley & Sons, Inc.