Targeting Alp7/TACC to the spindle pole body is essential for mitotic spindle assembly in fission yeast

•Fission yeast Alp7 is a member of the conserved TACC protein family.•Amino acid residues within the TACC domain required for SPB targeting are identified.•SPB localisation of Alp7 is essential for proper spindle assembly.•Pericentrin-related Pcp1 acts as one of the platforms for Alp7 recruitment during mitosis. The conserved TACC protein family localises to the centrosome (the spindle pole body, SPB in fungi) and mitotic spindles, thereby playing a crucial role in bipolar spindle assembly. However, it remains elusive how TACC proteins are recruited to the centrosome/SPB. Here, using fission yeast Alp7/TACC, we have determined clustered five amino acid residues within the TACC domain required for SPB localisation. Critically, these sequences are essential for the functions of Alp7, including proper spindle formation and mitotic progression. Moreover, we have identified pericentrin-like Pcp1 as a loading factor to the mitotic SPB, although Pcp1 is not a sole platform. Alp14 and Alp7colocalize by fluorescence microscopy (View interaction) Alp4 and Alp7colocalize by fluorescence microscopy (View interaction) Alp7 and Pcp1colocalize by fluorescence microscopy (View interaction) Alp7physically interacts with Pcp1 by anti tag coimmunoprecipitation (View interaction) Pcp1physically interacts with Alp7 by anti bait coip (View interaction)