AUX1-mediated root hair auxin influx governs SCF^TIR1/AFB-type Ca²⁺ signaling.

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, in Arabidopsis root hairs. Using intracellular microelectrodes we show membrane depolarization, in response to IAA in a concentration- and pH-dependent manner. This depolarization is strongly impaired in aux1 mutants, 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 S

SUBMITTER: Dindas J 

PROVIDER: S-EPMC5862985 | biostudies-literature | 2018 Mar

REPOSITORIES: biostudies-literature