6v6d
From Proteopedia
Cryo-EM structure of human pannexin 1
Structural highlights
FunctionPANX1_HUMAN Structural component of the gap junctions and the hemichannels. May play a role as a Ca(2+)-leak channel to regulate ER Ca(2+) homeostasis.[1] [2] Publication Abstract from PubMedThe plasma membrane adenosine triphosphate (ATP) release channel pannexin 1 (PANX1) has been implicated in many physiological and pathophysiological processes associated with purinergic signaling, including cancer progression, apoptotic cell clearance, inflammation, blood pressure regulation, oocyte development, epilepsy and neuropathic pain. Here we present near-atomic-resolution structures of human and frog PANX1 determined by cryo-electron microscopy that revealed a heptameric channel architecture. Compatible with ATP permeation, the transmembrane pore and cytoplasmic vestibule were exceptionally wide. An extracellular tryptophan ring located at the outer pore created a constriction site, potentially functioning as a molecular sieve that restricts the size of permeable substrates. The amino and carboxyl termini, not resolved in the density map, appeared to be structurally dynamic and might contribute to narrowing of the pore during channel gating. In combination with functional characterization, this work elucidates the previously unknown architecture of pannexin channels and establishes a foundation for understanding their unique channel properties. Cryo-EM structures of the ATP release channel pannexin 1.,Deng Z, He Z, Maksaev G, Bitter RM, Rau M, Fitzpatrick JAJ, Yuan P Nat Struct Mol Biol. 2020 Apr;27(4):373-381. doi: 10.1038/s41594-020-0401-0. Epub, 2020 Mar 30. PMID:32231289[3] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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Categories: Homo sapiens | Large Structures | Deng Z | He Z | Yuan P