Specialist α-tubulins for pluralist microtubules.

α- and β-tubulins are encoded by multigene families, but the role of tubulin diversity for microtubule function has been a longstanding mystery. A new study (2021. J. Cell Biol.https://doi.org/10.1083/jcb.202010155) shows that the two budding yeast α-tubulins have distinct roles during mitotic spindle positioning.