7P5W

Structure of homomeric LRRC8A Volume-Regulated Anion Channel in complex with synthetic nanobody Sb2

Summary for 7P5W

• Entry DOI: 10.2210/pdb7p5w/pdb
• EMDB information: 13202 13203
• Descriptor: Volume-regulated anion channel subunit LRRC8A, synthetic nanobody Sb2 (2 entities in total)
• Functional Keywords: lrrc8 family, volume-regulated anion channel, leucine-rich repeat, sybody, cryo-em, membrane protein
• Biological source: Mus musculus (Mouse); More
• Total number of polymer chains: 12
• Total formula weight: 665925.95

Authors

Deneka, D.,Rutz, S.,Sawicka, M. (deposition date: 2021-07-15, release date: 2021-09-15, Last modification date: 2021-10-13)

Primary citation

Deneka, D.,Rutz, S.,Hutter, C.A.J.,Seeger, M.A.,Sawicka, M.,Dutzler, R.
Allosteric modulation of LRRC8 channels by targeting their cytoplasmic domains.
Nat Commun, 12:5435-5435, 2021

PubMed Abstract: Members of the LRRC8 family form heteromeric assemblies, which function as volume-regulated anion channels. These modular proteins consist of a transmembrane pore and cytoplasmic leucine-rich repeat (LRR) domains. Despite their known molecular architecture, the mechanism of activation and the role of the LRR domains in this process has remained elusive. Here we address this question by generating synthetic nanobodies, termed sybodies, which target the LRR domain of the obligatory subunit LRRC8A. We use these binders to investigate their interaction with homomeric LRRC8A channels by cryo-electron microscopy and the consequent effect on channel activation by electrophysiology. The five identified sybodies either inhibit or enhance activity by binding to distinct epitopes of the LRR domain, thereby altering channel conformations. In combination, our work provides a set of specific modulators of LRRC8 proteins and reveals the role of their cytoplasmic domains as regulators of channel activity by allosteric mechanisms.

PubMed: 34521847
DOI: 10.1038/s41467-021-25742-w

Experimental method

ELECTRON MICROSCOPY (3.5 Å)