The mother-bud neck as a signaling platform for the coordination between spindle position and cytokinesis in budding

Laura Merlini1, Simonetta Piatti

  • 1Dipartimento di Biotecnologie e Bioscienze, Università di Milano-Bicocca, Milan, Italy.

Biological Chemistry
|August 10, 2011
PubMed

During asymmetric cell division, spindle positioning is critical for ensuring the unequal inheritance of polarity factors. In budding yeast, the mother-bud neck determines the cleavage plane and a correct nuclear division between mother and daughter cell requires orientation of the mitotic spindle along the mother-bud axis. A surveillance device called the spindle position/orientation checkpoint (SPOC) oversees this process and delays mitotic exit and cytokinesis until the spindle is properly oriented along the division axis, thus ensuring genome stability. Cytoskeletal proteins called septins form a ring at the bud neck that is essential for cytokinesis. Furthermore, septins and septin-associated proteins are implicated in spindle positioning and SPOC. In this review, we discuss the emerging connections between septins and the SPOC and the role of the mother-bud neck as a signaling platform to couple proper chromosome segregation to cytokinesis.

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