| Title | Structural organization of Weibel-Palade bodies revealed by cryo-EM of vitrified endothelial cells. | | Author(s) | Berriman JA, Li S, Hewlett LJ, Wasilewski S, Kiskin FN, Carter T, Hannah MJ, Rosenthal PB | | Institution | Divisions of Physical Biochemistry and Molecular Neuroendocrinology, MRC National Institute for Medical Research, The Ridgeway, Mill Hill, London, NW7 1AA, United Kingdom. | | Source | Proc Natl Acad Sci U S A 2009 Sep 29. | | Abstract | In endothelial cells, the multifunctional blood glycoprotein von Willebrand Factor (VWF) is stored for rapid exocytic release in specialized secretory granules called Weibel-Palade bodies (WPBs). Electron cryomicroscopy at the thin periphery of whole, vitrified human umbilical vein endothelial cells (HUVECs) is used to directly image WPBs and their interaction with a 3D network of closely apposed membranous organelles, membrane tubules, and filaments. Fourier analysis of images and tomographic reconstruction show that VWF is packaged as a helix in WPBs. The helical signature of VWF tubules is used to identify VWF-containing organelles and characterize their paracrystalline order in low dose images. We build a 3D model of a WPB in which individual VWF helices can bend, but in which the paracrystalline packing of VWF tubules, closely wrapped by the WPB membrane, is associated with the rod-like morphology of the granules. | | Language | ENG | | Pub Type(s) | JOURNAL ARTICLE
| | PubMed ID | 19805028 |
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