title: Clathrin light chains regulate clathrin-mediated trafficking, auxin signaling, and development in Arabidopsis.
abstract: Plant clathrin-mediated membrane trafficking is involved in many developmental processes as well as in responses to environmental cues. Previous studies have shown that clathrin-mediated endocytosis of the plasma membrane (PM) auxin transporter PIN-FORMED1 is regulated by the extracellular auxin receptor AUXIN BINDING PROTEIN1 (ABP1). However, the mechanisms by which ABP1 and other factors regulate clathrin-mediated trafficking are poorly understood. Here, we applied a genetic strategy and time-resolved imaging to dissect the role of clathrin light chains (CLCs) and ABP1 in auxin regulation of clathrin-mediated trafficking in Arabidopsis thaliana. Auxin was found to differentially regulate the PM and trans-Golgi network/early endosome (TGN/EE) association of CLCs and heavy chains (CHCs) in an ABP1-dependent but TRANSPORT INHIBITOR RESPONSE1/AUXIN-BINDING F-BOX PROTEIN (TIR1/AFB)-independent manner. Loss of CLC2 and CLC3 affected CHC membrane association, decreased both internalization and intracellular trafficking of PM proteins, and impaired auxin-regulated endocytosis. Consistent with these results, basipetal auxin transport, auxin sensitivity and distribution, and root gravitropism were also found to be dramatically altered in clc2 clc3 double mutants, resulting in pleiotropic defects in plant development. These results suggest that CLCs are key regulators in clathrin-mediated trafficking downstream of ABP1-mediated signaling and thus play a critical role in membrane trafficking from the TGN/EE and PM during plant development.
authors: College of Chemistry and Life Sciences, Zhejiang Normal University, Zhejiang 321004, China.
authors: Chao
authors: C
authors: Wang
authors: Xu
authors: X
authors: Yan
authors: Qian
authors: Q
authors: Chen
authors: Nan
authors: N
authors: Jiang
authors: Wei
authors: W
authors: Fu
authors: Bojun
authors: B
authors: Ma
authors: Jianzhong
authors: J
authors: Liu
authors: Chuanyou
authors: C
authors: Li
authors: Sebastian Y
authors: SY
authors: Bednarek
authors: Jianwei
authors: J
authors: Pan
mesh_terms: D017360:Arabidopsis / Q000166:cytology / Q000187:drug effects / Q000254:growth & development* / Q000378:metabolism; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D002462:Cell Membrane / Q000187:drug effects / Q000378:metabolism; D033922:Clathrin Heavy Chains / Q000235:genetics / Q000378:metabolism; D033941:Clathrin Light Chains / Q000235:genetics / Q000378:metabolism*; D003513:Cycloheximide / Q000494:pharmacology; D011992:Endosomes / Q000378:metabolism; D044783:F-Box Proteins / Q000378:metabolism; D018522:Gravitropism / Q000502:physiology; D007210:Indoleacetic Acids / Q000378:metabolism*; D007976:Leupeptins / Q000494:pharmacology; D009154:Mutation; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism; D030821:Plants, Genetically Modified; D011956:Receptors, Cell Surface / Q000235:genetics / Q000378:metabolism; D015398:Signal Transduction; D021601:trans-Golgi Network / Q000378:metabolism
chemical_list: D029681:Arabidopsis Proteins; D033941:Clathrin Light Chains; D044783:F-Box Proteins; D007210:Indoleacetic Acids; D007976:Leupeptins; D010940:Plant Proteins; D011956:Receptors, Cell Surface; C501405:TIR1 protein, Arabidopsis; C083846:auxin-binding protein 1; D033922:Clathrin Heavy Chains; D003513:Cycloheximide; C072553:benzyloxycarbonylleucyl-leucyl-leucine aldehyde