Year: 2018
Type: article
Abstract: Auxin is a key regulator of plant growth and development, but the causal relationship between hormone transport and root responses remains unresolved. Here we describe auxin uptake, together with early steps in signaling, inArabidopsisroot hairs. Using intracellular microelectrodes we show membrane depolarization, in response to IAA in a concentration- and pH-dependent manner. This depolarization is strongly impaired inaux1mutants, indicating that AUX1 is the major transporter for auxin uptake in root hairs. Local intracellular auxin application triggers Ca2+signals that propagate as long-distance waves between root cells and modulate their auxin responses. AUX1-mediated IAA transport, as well as IAA-triggered calcium signals, are blocked by treatment with the SCFTIR1/AFB- inhibitor auxinole. Further, they are strongly reduced in thetir1afb2afb3and thecngc14mutant. Our study reveals that the AUX1 transporter, the SCFTIR1/AFBreceptor and the CNGC14 Ca2+channel, mediate fast auxin signaling in roots.
Source: Nature Communications
Language: English
Subfield: Plant Science
Domain: Life Sciences
Open Access status: gold
Estimated APC paid: $6,990
OpenAlex ID: W2789294653