X-linked doublecortin (DCX), a neuron-specific microtubule-associated protein, plays vital roles in microtubule organization. DCX directly binds to microtubules via its two evolutionarily conserved, structured doublecortin (DC) domains, N-DC and C-DC, and this interaction has been proposed to be regulated by flanking regions of the DCX N-terminus and the C-terminus. Although DCX is known to regulate microtubule function, its precise mechanism of action is yet to be determined. In our study, we are investigating the role of DCX in microtubule organization and microtubule-dependent events including neuronal migration through studying the effects of DCX truncations (ΔN, ΔC and the combined ΔN + ΔC DCX deletions) as well as pathogenic mutations within the N-DC and DCX N-terminal regions. Our confocal imaging results indicate that DCX is able to bundle microtubules and that this effect is disrupted in the absence of the DCX N-terminal region. Two recently identified pathogenic mutations in the N-terminal regions of DCX (E2K and D9N) and two mutants within the N-DC domain (R89G and R102S) have been studied and our results so far have indicated that E2K and D9N showed the same behaviour as full-length DCX in term of induction of microtubule bundling while mutations in the N-DC, R89G and R102S reduced the bundling ability of DCX. Taken together, these results emphasize the critical regulation of microtubule organization by DCX but the need for further investigations of the role of DCX in the modulation of microtubule organization to improve our understanding of the pathogenesis of neuronal migration disorders.