Arabidopsis ADF8 and ADF11 Contribute to Root Hair Growth to Respond to Hormone and Environmental Signals

The study investigates the role of Arabidopsis actin-depolymerizing factors ADF8 and ADF11 in root hair growth, highlighting their importance in responding to hormonal and environmental signals. These factors are expressed in root hairs and are induced by auxin and ethylene. The research shows that root hairs lacking ADF8 and ADF11 have reduced sensitivity to these hormones and fail to maintain the necessary F-actin meshwork at the root hair tip. Additionally, ADF8/11 are involved in root hair elongation under low-phosphate and low-nitrogen conditions. The study identifies transcription factors RSL4, auxin-responsive ARFs, and ethylene-responsive EIN3 as regulators of ADF8/11 expression, establishing a direct link between hormonal signaling and F-actin dynamics in root hairs.