Kinase interplay centered on two regulatory elements compartmentalizes the checkpoint protein Lte1 in S. cerevisiae.

Lte1 compartmentalization at the bud cortex in budding yeast depends on two phospho-regulatory elements, N- and C-Lte1 regulatory elements, to ensure timely mitotic exit.

• Why it matters: Correct chromosomal segregation across the bud neck requires Lte1 to be confined to the bud, but how kinase signaling programs this spatial checkpoint control is unclear.
• What they did: The study mapped an Lte1 domain for Ras binding and two phospho-regulatory motifs, showing C-LRE control via Cla4 and N-LRE phosphorylation by Kin1/2, alongside cyclin-dependent kinase sites.
• The result: N- and C-LREs, together with CDK phosphorylation sites, are required for Lte1 localization and timely mitotic exit, revealing kinase interplay that integrates polarity and cell-cycle cues for strict bud cortical compartmentalization.