Characterization of auxin transporter PIN6 plasma membrane targeting reveals a function for PIN6 in plant bolting

Citations Over TimeTop 10% of 2017 papers

Abstract

Auxin gradients are sustained by series of influx and efflux carriers whose subcellular localization is sensitive to both exogenous and endogenous factors. Recently the localization of the Arabidopsis thaliana auxin efflux carrier PIN-FORMED (PIN) 6 was reported to be tissue-specific and regulated through unknown mechanisms. Here, we used genetic, molecular and pharmacological approaches to characterize the molecular mechanism(s) controlling the subcellular localization of PIN6. PIN6 localizes to endomembrane domains in tissues with low PIN6 expression levels such as roots, but localizes at the plasma membrane (PM) in tissues with increased PIN6 expression such as the inflorescence stem and nectary glands. We provide evidence that this dual localization is controlled by PIN6 phosphorylation and demonstrate that PIN6 is phosphorylated by mitogen-activated protein kinases (MAPKs) MPK4 and MPK6. The analysis of transgenic plants expressing PIN6 at PM or in endomembrane domains reveals that PIN6 subcellular localization is critical for Arabidopsis inflorescence stem elongation post-flowering (bolting). In line with a role for PIN6 in plant bolting, inflorescence stems elongate faster in pin6 mutant plants than in wild-type plants. We propose that PIN6 subcellular localization is under the control of developmental signals acting on tissue-specific determinants controlling PIN6-expression levels and PIN6 phosphorylation.

Related Papers

• → QTL for delayed bolting after winter detected in leaf beet (Beta vulgaris L.)(2017)11 cited
• → Bolting of sugar beet grown in England(1975)20 cited
• Effect of Temperature and Daylength on Growth and Bolting of Angelica gigas NAKAI(1994)
• → Breeding of Bolting Resistance in Chinese Cabbage. Critical Day Length for Flower Induction of Late Bolting Material with No Chilling Requirement.(1992)10 cited
• → Some effects of infection with yellowing viruses and of fungicide applications on bolting in sugar beet(1967)1 cited