Meikin synergizes with shugoshin to protect cohesin Rec8 during meiosis I

The conserved meiosis-specific kinetochore regulator, meikin (Moa1 in fission yeast) plays a central role in establishing meiosis-specific kinetochore function. However, the underlying molecular mechanisms remain elusive. Here, we show how Moa1 regulates centromeric cohesion protection, a function that has been previously attributed to shugoshin (Sgo1). Moal is known to associate with Plo1 kinase. We explore Plol-dependent Rec8 phosphorylation and identify a key phosphorylation site required for cohesion protection. The phosphorylation of Rec8 by Moa1-Plo1 potentiates the activity of PP2A associated with Sgo1. This leads to dephosphorylation of Rec8 at another site, which thereby prevents cleavage of Rec8 by separase.

Automated summary

The study elucidates the molecular mechanisms of Moa1 in regulating centromeric cohesion protection by associating with Plo1 kinase to control Rec8 phosphorylation, enhancing the activity of PP2A associated with Sgo1, and preventing the cleavage of Rec8 by separase through dephosphorylation at another site.