کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
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2044363 | 1073418 | 2009 | 7 صفحه PDF | دانلود رایگان |
![عکس صفحه اول مقاله: Fluorescence Imaging-Based Screen Identifies ARF GEF Component of Early Endosomal Trafficking Fluorescence Imaging-Based Screen Identifies ARF GEF Component of Early Endosomal Trafficking](/preview/png/2044363.png)
SummaryEndocytic vesicle trafficking is crucial for regulating activity and localization of plasma membrane components, but the process is still poorly genetically defined in plants. Membrane proteins of the PIN-FORMED (PIN) family exhibit polar localization in plant cells and facilitate cellular efflux of the plant hormone auxin, thereby regulating multiple developmental processes 1 and 2. PIN proteins undergo constitutive endocytosis and GNOM ARF GEF-dependent recycling 3, 4 and 5, and their localization is under extensive regulation by developmental and environmental cues 6, 7, 8 and 9. We designed a fluorescence imaging-based screen to identify Arabidopsis thaliana mutants defective in internalization of proteins including PINs from the plasma membrane. We identified three mutant loci, BFA-visualized endocytic trafficking defective1 (ben1) through ben3 that do not efficiently accumulate PIN1-GFP in intracellular compartments after inhibition of recycling and secretion by fungal toxin brefeldin A (BFA). Fine mapping revealed that BEN1 encodes an ARF GEF vesicle trafficking regulator from the functionally uncharacterized BIG class. ben1 mutant has been previously implicated in pathogen response [10] and shows cell polarity, BFA sensitivity, and growth defects. BEN1 is involved in endocytosis of plasma membrane proteins and localizes to early endocytic compartments distinct from GNOM-positive endosomes. Our results identify BEN1 as the ARF GEF mediating early endosomal traffic.
Journal: - Volume 19, Issue 5, 10 March 2009, Pages 391–397