ZNRF1 interacts with tubulin and regulates cell morphogenesis

The ubiquitin–proteasome system has been implicated in neuronal degeneration and regeneration. We demonstrated that overexpression of ZNRF1, which has been identified as a crucial molecule in nerve regeneration, causes morphological changes such as neurite-like elongation. Molecular dissections showed that both the RING finger domain and zinc finger domain are required for morphological changes. Furthermore, we identified β-tubulin type 2 (Tubb2) as a ZNRF1-binding protein by yeast two-hybrid screening. In vivo binding assay showed that ZNRF1 interacts with Tubb2 and immunofluorescent staining suggests that ZNRF1 is colocalized with Tubb2. These results suggest that ZNRF1 mediates regulation of neuritogenesis via interaction with tubulin.