Open AccessTubZ filament assembly dynamics requires the flexible C-terminal tail
Author(s) -
M. Fuentes-Pérez,
Rafael Núñez-Ramírez,
Alejandro Martín-González,
David Juan-Rodríguez,
Óscar Llorca,
Fernando MorenoHerrero,
M.A. Oliva
Publication year - 2017
Publication title -
scientific reports
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.24
H-Index - 213
ISSN - 2045-2322
DOI - 10.1038/srep43342
Subject(s) - protein filament , treadmilling , biophysics , atp hydrolysis , cytoskeleton , intermediate filament , biology , microbiology and biotechnology , chemistry , biochemistry , cell , microfilament , atpase , enzyme
Cytomotive filaments are essential for the spatial organization in cells, showing a dynamic behavior based on nucleotide hydrolysis. TubZ is a tubulin-like protein that functions in extrachromosomal DNA movement within bacteria. TubZ filaments grow in a helical fashion following treadmilling or dynamic instability, although the underlying mechanism is unclear. We have unraveled the molecular basis for filament assembly and dynamics combining electron and atomic force microscopy and biochemical analyses. Our findings suggest that GTP caps retain the filament helical structure and hydrolysis triggers filament stiffening upon disassembly. We show that the TubZ C-terminal tail is an unstructured domain that fulfills multiple functions contributing to the filament helical arrangement, the polymer remodeling into tubulin-like rings and the full disassembly process. This C-terminal tail displays the binding site for partner proteins and we report how it modulates the interaction of the regulator protein TubY.