Cryo-EM structures of the Plant Augmin reveal its intertwined coiled-coil assembly, antiparallel dimerization and NEDD1 binding mechanisms.

ABSTRACT: Microtubule (MT) branch nucleation is fundamental for building parallel MT networks in eukaryotic cells. In plants and metazoans, MT branch nucleation requires Augmin and NEDD1 proteins which bind along MTs and then recruit and activate the gamma-tubulin ring complex (γ-TuRC). Augmin is a fork-shaped assembly composed of eight coiled-coil subunits, while NEDD1 is a WD40 β-propellor protein that bridges across MTs, Augmin, and γ-TuRC during MT branch nucleation. Here, we reconstitute hetero-tetrameric and hetero-octameric Arabidopsis thaliana Augmin assemblies, resolve their subunit interactions using crosslinking mass spectrometry and determine 3.7 to 7.3-Å cryo-EM structures for the V-junction and extended regions of Augmin. These structures allowed us to generate a complete de novo plant

SUBMITTER: Ashaduzzaman M 

PROVIDER: S-EPMC11875243 | biostudies-literature | 2025 Feb

REPOSITORIES: biostudies-literature