This N-terminal domain of BBP1, a spindle pole body component, interacts directly, though transiently, with the polo-box domain of Cdc5p. full length BBP1 localises at the cytoplasmic side of the central plaque periphery of the spindle pole body (SPB) and plays an important role in inserting a duplication plaque into the nuclear envelope and assembling a functional inner plaque [1]. Although not a membrane protein itself, BBP1 binds to Mps2 as well as to Spc29 and the half-bridge protein Kar1, thus providing a model for how the SPB core is tethered within the nuclear envelope and to the half-bridge [2].

1: Requirement for Bbp1p in the proper mitotic functions of Cdc5p in Saccharomyces cerevisiae. Park CJ, Song S, Giddings TH Jr, Ro HS, Sakchaisri K, Park JE, Seong YS, Winey M, Lee KS; Mol Biol Cell. 2004;15:1711-1723. PMID:14767068

2: The budding yeast spindle pole body: structure, duplication, and function. Jaspersen SL, Winey M; Annu Rev Cell Dev Biol. 2004;20:1-28. PMID:15473833