Defining auxin response contexts in plant development.

The apparent domination of so much of plant development by the hormone auxin raises important questions about how this simple, generic signalling molecule can give rise to such an enormous range of very specific developmental outputs. What is becoming increasingly clear is that alongside the tight control of auxin distribution within the plant, the cellular and developmental context in which the auxin signal is received is of utmost importance. Recent work has highlighted that these distinct auxin response contexts are defined by complex and inter-dependent relationships between auxin metabolism, transport and response that can be modulated at many levels by inputs from both endogenous and environmental signals. Copyright 2009 Elsevier Ltd. All rights reserved.