Spastin's Microtubule-Binding Properties and Comparison to Katanin
Panel A displays the constructs used for katanin binding experiments. Panel B shows a quantitative SDS-gel of supernatants (unbound) and pellets (microtubule-bound) of an in vitro binding assay of truncated katanin constructs and microtubules. Increasing microtubule concentrations (0 to 10 µM) were incubated with a fixed katanin construct concentration (1 µM). The density of the katanin construct band was plotted against the microtubule concentration and fitted to a Hill function (panel C). The half-maximal saturation was reached at 0.34 µM (Kat12) and 0.40 µM (Kat2). Only constructs containing domain 2 were able to bind to microtubules.