Regulation of microtubule organization and functions by septin GTPases

Septins comprise an evolutionarily conserved family of oligomeric GTPases that regulate the intracellular localization of proteins by functioning as protein scaffolds and diffusion barriers. Recent studies reveal that septins associate with microtubules, microtubule-associated proteins (MAPs), and microtubule motors. Here, I review these findings and consider how septins may spatially regulate the interaction of microtubules with MAPs and motor proteins. Thus, septins may constitute a novel regulatory module of microtubule organization and function with important implications in the understanding and treatment of cancer and neurodegeneration.