2011-06-28Zeitschriftenartikel DOI: 10.1073/pnas.1101707108
Molecular in situ topology of Aczonin/Piccolo and associated proteins at the mammalian neurotransmitter release site
Kilimann, Manfred W.
The protein machinery of neurotransmitter exocytosis requires efficient orchestration in space and time, for speed and precision of neurotransmission and also for synaptic ontogeny and plasticity. However, its spatial organization in situ is virtually unknown. Aczonin/Piccolo is a putative organizer protein of mammalian active zones. We determined by immunogold electron microscopy (EM) (i) the spatial arrangement (i.e., topology) of 11 segments of the Aczonin polypeptide in situ, and correlated it to (ii) the positioning of Aczonin-interacting domains of Bassoon, CAST/ELKS, Munc13, and RIM and (iii) the ultrastructurally defined presynaptic macromolecular aggregates known as dense projections and synaptic ribbons. At conventional synapses, Aczonin assumes a compact molecular topology within a layer 35 to 80 nm parallel to the plasma membrane (PM), with a "trunk" sitting on the dense projection top and a C-terminal "arm" extending down toward the PM and sideward to the dense projection periphery. At ribbon synapses, Aczonin occupies the whole ribbon area. Bassoon colocalizes with Aczonin at conventional synapses but not at ribbon synapses. At both conventional and ribbon synapses, CAST, Munc13, and RIM are segregated from Aczonin, closer to the PM, and Aczonin is positioned such that it may control the access of neurotransmitter vesicles to the fusion site.
No license information
Show related Items with similar Title, Author, Creator or Subject.
2013-03-11ZeitschriftenartikelTowards further reduction and replacement of animal bioassays in prion research by cell and protein misfolding cyclic amplification assays Boerner, Susann; Wagenführ, Katja; Daus, Martin L.; Thomzig, Achim; Beekes, MichaelLaboratory animals have long since been used extensively in bioassays for prions in order to quantify, usually in terms of median infective doses [ID50], how infectious these pathogens are in vivo. The identification of ...
2012-12-21ZeitschriftenartikelProtein-Protein Interaction Domains of Bacillus subtilis DivIVA Baarle, Suey van; Celik, Ilkay Nazli; Kaval, Karan Gautam; Bramkamp, Marc; Hamoen, Leendert W.; Halbedel, SvenDivIVA proteins are curvature-sensitive membrane binding proteins that recruit other proteins to the poles and the division septum. They consist of a conserved N-terminal lipid binding domain fused to a less conserved ...
2013-08-08ZeitschriftenartikelCytomegalovirus Downregulates IRE1 to Repress the Unfolded Protein Response Stahl, Sebastian; Burkhart, Julia M.; Hinte, Florian; Tirosh, Boaz; Mohr, Hermine; Zahedi, René P.; Sickmann, Albert; Ruzsics, Zsolt; Budt, Matthias; Brune, WolframDuring viral infection, a massive demand for viral glycoproteins can overwhelm the capacity of the protein folding and quality control machinery, leading to an accumulation of unfolded proteins in the endoplasmic reticulum ...