Component of the spindle pole body (SPB) required for the proper execution of spindle pole body (SPB) duplication. Links the central plaque component SPC42 to the inner plaque component SPC110. Component of the SPC110 complex containing at least CMD1, SPC29, SPC42 and SCP110. Interacts with BBP1. MPS1-mediated phosphorylation at Thr-240 is required for spindle pole body duplication. Belongs to the SPC29 family.