title: Budding Yeast Sae2 is an In Vivo Target of the Mec1 and Tel1 Checkpoint Kinases During Meiosis.
abstract: DNA double-strand breaks (DSBs) are introduced into the genome to initiate meiotic recombination. Their accurate repair is monitored by the meiotic recombination checkpoint that prevents nuclear division until completion of meiotic DSB repair. We show that the Saccharomyces cerevisiae Sae2 protein, known to be involved in processing meiotic DSBs, is phosphorylated periodically during the meiotic cycle. Sae2 phosphorylation occurs at the onset of premeiotic S phase, is maximal at the time of meiotic DSB generation and decreases when DSBs are repaired by homologous recombination. Hyperactivation of the meiotic recombination checkpoint caused by the failure to repair DSBs results in accumulation and persistence of phosphorylated Sae2, indicating a possible link between checkpoint activation and meiosis-induced Sae2 phosphorylation. Accordingly, Sae2 phosphorylation depends on the checkpoint kinases Mec1 and Tel1, whose simultaneous deletion also impairs meiotic DSB repair. Moreover, replacing with alanines the Sae2 serine and threonine residues belonging to Mec1/Tel1-dependent putative phosphorylation sites impairs not only Sae2 phosphorylation during meiosis, but also meiotic DSB repair. Thus, checkpoint-mediated phosphorylation of Sae2 is important to support its meiotic recombination functions.
authors.affiliation: Dipartimento di Biotecnologie e Bioscienze, Università degli Studi di Milano-Bicocca, Milan, Italy.
authors.forename: Hugo
authors.initials: H
authors.lastname: Cartagena-Lirola
authors.forename: Ilaria
authors.initials: I
authors.lastname: Guerini
authors.forename: Valeria
authors.initials: V
authors.lastname: Viscardi
authors.forename: Giovanna
authors.initials: G
authors.lastname: Lucchini
authors.forename: Maria Pia
authors.initials: MP
authors.lastname: Longhese
mesh_terms: D018797:Cell Cycle Proteins / Q000378:metabolism / Q000502:physiology; D004260:DNA Repair; D004720:Endonucleases; D005656:Fungal Proteins / Q000378:metabolism* / Q000502:physiology; D047908:Intracellular Signaling Peptides and Proteins; D008540:Meiosis; D010766:Phosphorylation; D017346:Protein Serine-Threonine Kinases; D011995:Recombination, Genetic; D029701:Saccharomyces cerevisiae Proteins / Q000378:metabolism* / Q000502:physiology
chemical_list: D018797:Cell Cycle Proteins; D005656:Fungal Proteins; D047908:Intracellular Signaling Peptides and Proteins; C107849:SAE2 protein, S cerevisiae; D029701:Saccharomyces cerevisiae Proteins; C088937:MEC1 protein, S cerevisiae; D017346:Protein Serine-Threonine Kinases; C513623:TEL1 protein, S cerevisiae; D004720:Endonucleases