6WC9

Human open state TMEM175 in KCl

Summary for 6WC9

• Entry DOI: 10.2210/pdb6wc9/pdb
• EMDB information: 21603 21604 21605 21606
• Descriptor: Endosomal/lysosomal potassium channel TMEM175, POTASSIUM ION (3 entities in total)
• Functional Keywords: ion channel, lysosome, potassium channel, transport protein
• Biological source: Homo sapiens (Human)
• Total number of polymer chains: 2
• Total formula weight: 111608.12

Authors

Oh, S.,Paknejad, N.,Hite, R.K. (deposition date: 2020-03-30, release date: 2020-04-15, Last modification date: 2024-03-06)

Primary citation

Oh, S.,Paknejad, N.,Hite, R.K.
Gating and selectivity mechanisms for the lysosomal K + channel TMEM175.
Elife, 9:-, 2020

PubMed Abstract: Transmembrane protein 175 (TMEM175) is a K-selective ion channel expressed in lysosomal membranes, where it establishes a membrane potential essential for lysosomal function and its dysregulation is associated with the development of Parkinson's Disease. TMEM175 is evolutionarily distinct from all known channels, predicting novel ion-selectivity and gating mechanisms. Here we present cryo-EM structures of human TMEM175 in open and closed conformations, enabled by resolutions up to 2.6 Å. Human TMEM175 adopts a homodimeric architecture with a central ion-conduction pore lined by the side chains of the pore-lining helices. Conserved isoleucine residues in the center of the pore serve as the gate in the closed conformation. In the widened channel in the open conformation, these same residues establish a constriction essential for K selectivity. These studies reveal the mechanisms of permeation, selectivity and gating and lay the groundwork for understanding the role of TMEM175 in lysosomal function.

PubMed: 32228865
DOI: 10.7554/eLife.53430

Experimental method

ELECTRON MICROSCOPY (2.64 Å)