Auxin receptors and perception

Abstract

Auxin perception initiates auxin action and is the key step for controlled plant growth and development. The term perception implies two linked processes: auxin binding and the biological reaction to that binding event. In human terms we might describe these steps as recognition and interpretation. Auxin signalling has become a collective description for all the various mechanisms driving interpretation and often may be only indirectly and distantly connected to perception. Other chapters will describe how plants interpret auxin perception and the multitude of auxin-driven responses we recognise during development. In this chapter, we will examine what has been learnt about auxin-binding sites and link these observations to early signalling events, the immediate consequences of binding. Signal amplification progresses through, for example, genetic cascades will not be considered here because they are covered in other chapters, particularly under Auxin and Plant Development (see Chaps. 7 - 14). Signals linked to perception by biochemical events are considered briefly because these open up the discussion about the probability of additional classes of receptor, including ABP1.