Transcriptional Control of the Plant Cell Cycle 29
sitions, or as executors of phase-specific waves of gene expression, does not
sufficiently account for the regulatory interactions observed in cells or the in-
terdependence of these processes. In contrast, our current knowledge is much
more consistent with the view that these processes comprise closed regulatory
cycles that are interlocked and coupled with each other through numerous reg-
ulatory interactions. With advances at the technological and conceptual level,
there are now exciting opportunities to characterize these regulatory circuits
in unprecedented detail. This will lead to a better mechanistic understanding
of plant cell cycle control, and enable new approaches to modify plant growth
and increase agricultural productivity in the service of human welfare.
AcknowledgementsThe support of the Biotechnology and Biological Sciences Research
Council (BBSRC), the Royal Society, the Darwin Trust, and the Samuel Roberts Noble
Foundation for work in the Doerner Lab is gratefully acknowledged. I gratefully acknowl-
edge all stimulating discussions with present and former members of the laboratory. I
apologize to colleagues whose work was not mentioned due to space restrictions.
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