EEF1B2 interacts with KATNA1 to potentiate microtubule severing and neurite outgrowth

Cytoskeletal remodeling, including microtubule severing, is essential for neurite growth and structural plasticity. However, the regulatory mechanisms that control the microtubule-severing activity of katanin A1 (KATNA1) remain incompletely understood. Here, we identify a novel interaction between eukaryotic translation elongation factor 1 beta (EEF1B2) and KATNA1 and show that this protein pair regulates microtubule dynamics and neurite outgrowth. Proteomic screening and biochemical validation (GST pull-down and co-immunoprecipitation) demonstrated that EEF1B2 interacted with KATNA1, with strongest binding mapped to the KATNA1 AAA + ATPase domain. In COS7 cells, EEF1B2 potentiated KATNA1-dependent microtubule severing, whereas EEF1B2 knockdown attenuated KATNA1-driven microtubule loss. In primary cortical neurons, EEF1B2 enhanced KATNA1-induced neurite outgrowth and branching, and these effects were KATNA1-dependent. Together, these findings identify EEF1B2 as a modulator of KATNA1 activity and provide new insight into the molecular mechanisms governing microtubule remodeling and neurite growth.