Polar subcellular localization of the PIN exporters of the phytohormone auxin is a key determinant of directional, intercellular auxin transport and thus a central topic of both plant cell and... Show morePolar subcellular localization of the PIN exporters of the phytohormone auxin is a key determinant of directional, intercellular auxin transport and thus a central topic of both plant cell and developmental biology. Arabidopsis mutants lacking PID, a kinase that phosphorylates PINs, or the MAB4/MEL proteins of unknown molecular function display PIN polarity defects and phenocopy pin mutants, but mechanistic insights into howthese factors convey PIN polarity are missing. Here, by combining protein biochemistry with quantitative live-cell imaging, we demonstrate that PINs, MAB4/MELs, and AGC kinases interact in the same complex at the plasma membrane. MAB4/MELs are recruited to the plasma membrane by the PINs and in concert with the AGC kinases maintain PIN polarity through limiting lateral diffusion-based escape of PINs from the polar domain. The PIN-MAB4/MEL-PID protein complex has self-reinforcing properties thanks to positive feedback between AGC kinase-mediated PIN phosphorylation and MAB4/MEL recruitment. Wethus uncover the molecular mechanism by which AGC kinases and MAB4/MEL proteins regulate PIN localization and plant development. Show less
Hille, S.C.; Akhmanova, M.; Glanc, M.; Johnson, A.; Friml, J. 2018
The authors informed us of problems related to Fig. 3C and Fig. 7D in Development137, 3245-3255. Both issues were noted by an investigation by the Technical Committee of Utrecht University (UTC)... Show moreThe authors informed us of problems related to Fig. 3C and Fig. 7D in Development137, 3245-3255. Both issues were noted by an investigation by the Technical Committee of Utrecht University (UTC) into this publication. Based on the findings provided (detailed below), the journal has decided that the major conclusions of the paper are not affected and that retraction is not required, but that a correction should be provided with an explanation of the circumstances. This course of action complies with our policy on correction of issues in the scientific record, which states: “Should an error appear in a published article that affects scientific meaning or author credibility but does not affect the overall results and conclusions of the paper, our policy is to publish a Correction”.Development 2010 137: 3245-3255; doi: 10.1242/dev.052456 Show less
The apical hook of dark-grown Arabidopsis seedlings is a simple structure that develops soon after germination to protect the meristem tissues during emergence through the soil and that opens upon... Show moreThe apical hook of dark-grown Arabidopsis seedlings is a simple structure that develops soon after germination to protect the meristem tissues during emergence through the soil and that opens upon exposure to light. Differential growth at the apical hook proceeds in three sequential steps that are regulated by multiple hormones, principally auxin and ethylene. We show that the progress of the apical hook through these developmental phases depends on the dynamic, asymmetric distribution of auxin, which is regulated by auxin efflux carriers of the PIN family. Several PIN proteins exhibited specific, partially overlapping spatial and temporal expression patterns, and their subcellular localization suggested auxin fluxes during hook development. Genetic manipulation of individual PIN activities interfered with different stages of hook development, implying that specific combinations of PIN genes are required for progress of the apical hook through the developmental phases. Furthermore, ethylene might modulate apical hook development by prolonging the formation phase and strongly suppressing the maintenance phase. This ethylene effect is in part mediated by regulation of PIN-dependent auxin efflux and auxin signaling. Show less
Kleine-Vehn, J.; Huang, F.; Naramoto, J.; Zhang, J.; Offringa, R.; Michniewicz, M.; Friml, J. 2009
