Phosphosites of the yeast centrosome component Spc110 contribute to cell cycle progression and mitotic exit

Rewiring of the phosphoproteome executes two meiotic divisions in budding yeast

The cell cycle is ordered by a controlled network of kinases and phosphatases. To generate gametes via meiosis, two distinct and sequential chromosome segregation events occur without an intervening S phase. How canonical cell cycle controls are modified for meiosis is not well understood. Here, using highly synchronous budding yeast populations, we reveal how the global proteome and phosphoproteome change during the meiotic divisions. While protein abundance changes are limited to key cell cycle regulators, dynamic phosphorylation changes are pervasive. Our data indicate that two waves of cyclin-dependent kinase (Cdc28Cdk1) and Polo (Cdc5Polo) kinase activity drive successive meiotic divisions. These two distinct phases of phosphorylation are ensured by the meiosis-specific Spo13 protein, which rewires the phosphoproteome. Spo13 binds to Cdc5Polo to promote phosphorylation in meiosis I, particularly of substrates containing a variant of the canonical Cdc5Polo motif. Overall, our findings reveal that a master regulator of meiosis directs the activity of a kinase to change the phosphorylation landscape and elicit a developmental cascade.

First person – Marjan Abbasi

First Person is a series of interviews with the first authors of a selection of papers published in Biology Open, helping researchers promote themselves alongside their papers. Marjan Abbasi is first author on ‘ Phosphosites of the yeast centrosome component Spc110 contribute to cell cycle progression and mitotic exit’, published in BiO. Marjan is a PhD student in the lab of Victoria Menendez-Benito at the Karolinska Institutet, Bionut departement, Stockholm, Sweden, exploring the proteins involved in mitotic spindle regulation.