Plant separation: 50 ways to leave your mother.

One of the remarkable features of plants is their ability to shed organs, such as leaves, seeds, flowers, and fruit. Genetic analysis of fruit dehiscence and floral organ shedding in Arabidopsis is revealing the pathways that underlie these distinct separation events. The transcriptional network that patterns the fruit links factors that regulate organ polarity and growth with those that control differentiation of the three cell types that are required for dehiscence. Transcriptional regulators that pattern the proximal-distal axis in developing leaves are required for floral organ shedding, and chromatin-modifying complexes might globally regulate genes that affect flower senescence and abscission. Ground-breaking studies have also recently identified a hydrolytic enzyme that is required for microspore separation during pollen development, and the first transcription factor controlling seed abscission.