The phytohormone auxin acts as a key regulator of growth and development at every stage of a plant’s life cycle.
Canonical auxin signalling occurs through a pathway in which auxin molecules bind to TIR1/AFB F-box proteins, promoting their interaction with Aux/IAA repressor proteins and subsequently their degradation.
This repressor degradation leads to de-repression of Auxin Response Factors (ARFs) and expression of ARF target genes.
Recently, our group has found an alternative, non-canonical auxin signalling mechanism in which the atypical ARF, ETTIN (ETT/ARF3) physically interacts with diverse transcription factors (TFs) to regulate downstream targets in an auxin-sensitive manner.
This mechanism is important for coordinated gynoecium development. Andre’s project is to mechanistically understand how this non-canonical auxin signalling pathway works. To do so he uses a wide range of genetic and biochemical methods.