Signals, Motors, Morphogenesis - the Cytoskeleton in Plant Development*

Abstract

Plant shape can adapt to a changing environment. This requires a structure that (1) must be highly dynamic, (2) can respond to a range of signals, and (3) can control cellular morphogenesis. The cytoskeleton, microtubules, actin microfilaments, and cytoskeletal motors meets these requirements, and plants have evolved specific cytoskeletal arrays consisting of both microtubules and microfilaments that can link signal transduction to cellular morphogenesis: cortical microtubules, preprophase band, phragmoplast on the microtubular side, transvacuolar microfilament bundles, and phragmosome on the actin side. These cytoskeletal arrays are reviewed with special focus on the signal responses of higher plants. The signal-triggered dynamic response of the cytoskeleton must be based on spatial cues that organize assembly and disassembly of tubulin and actin. In this context the great morphogenetic potential of cytoskeletal motors is discussed. The review closes with an outlook on new methodological approaches to the problem of signal-triggered morphogenesis.

Key words

Actin microfilaments - cytoskeletal motors - cytoskeleton - microtubules - morphogenesis - signal transduction