During meiosis, crossover recombination is essential to link homologous chromosomes and drive faithful chromosome segregation. Crossover recombination is non-random across the genome, and centromere-proximal crossovers are associated with an increased risk of aneuploidy, including Trisomy 21 in humans. Here, we identify the conserved Ctf19/CCAN kinetochore sub-complex as a major factor that minimizes potentially deleterious centromere-proximal crossovers in budding yeast. We uncover multi-layered suppression of pericentromeric recombination by the Ctf19 complex, operating across distinct chromosomal distances. The Ctf19 complex prevents meiotic DNA break formation, the initiating event of recombination, proximal to the centromere. The Ctf19 complex independently drives the enrichment of cohesin throughout the broader pericentromere to suppress crossovers, but not DNA breaks. This non-canonical role of the kinetochore in defining a chromosome domain that is refractory to crossovers adds a new layer of functionality by which the kinetochore prevents the incidence of chromosome segregation errors that generate aneuploid gametes.DOI: http://dx.doi.org/10.7554/eLife.10850.001

In meiosis, DNA break formation and repair are essential for the formation of crossovers between homologous chromosomes. Without crossover formation, faithful meiotic chromosome segregation and sexual reproduction cannot occur. Crossover formation is initiated by the programmed, meiosis‐specific introduction of numerous DNA double‐strand breaks, after which specific repair pathways promote recombination between homologous chromosomes. Despite its crucial nature, meiotic recombination is fraud with danger: When positioned or repaired inappropriately, DNA breaks can have catastrophic consequences on genome stability of the resulting gametes. As such, DNA break formation and repair needs to be carefully controlled. Within centromeres and surrounding regions (i.e., pericentromeres), meiotic crossover recombination is repressed in organisms ranging from yeast to humans, and a failure to do so is implicated in chromosome missegregation and developmental aneuploidy. (Peri)centromere sequence identity and organization diverge considerably across eukaryotes, yet suppression of meiotic DNA break formation and repair appear universal. Here, we discuss emerging work that has used budding and fission yeast systems to study the mechanisms underlying pericentromeric suppression of DNA break formation and repair. We particularly highlight a role for the kinetochore, a universally conserved, centromere‐associated structure essential for chromosome segregation, in suppressing (peri)centromeric DNA break formation and repair. We discuss the current understanding of kinetochore‐associated and chromosomal factors involved in this regulation and suggest future avenues of research.

In meiosis, crossover formation between homologous chromosomes is essential for faithful segregation. However, misplaced meiotic recombination can have catastrophic consequences on genome stability. Within pericentromeres, crossovers are associated with meiotic chromosome missegregation. In organisms ranging from yeast to humans, pericentromeric crossovers are repressed. We previously identified a role for the kinetochore-associated Ctf19 complex (Ctf19c) in pericentromeric crossover suppression. Here, we develop a dCas9/CRISPR-based system that allows ectopic targeting of Ctf19c-subunits. Using this approach, we query sufficiency in meiotic crossover suppression, and identify Ctf19 as a mediator of kinetochore-associated crossover control. The effect of Ctf19 is encoded in its NH2-terminal tail, and depends on residues important for the recruitment of the Scc2-Scc4 cohesin regulator. This work provides insight into kinetochore-derived control of meiotic recombination. We establish an experimental platform to investigate and manipulate meiotic crossover control. This platform can easily be adapted in order to investigate other aspects of chromosome biology.

27In meiosis, crossover formation between homologous chromosomes is essential for 28 faithful segregation. However, improperly controlled or placed meiotic recombination can 29 have catastrophic consequences on genome stability. Specifically, within centromeres and 30 surrounding regions (i.e. pericentromeres), crossovers are associated with chromosome 31 missegregation and developmental aneuploidy. In organisms ranging from yeast to 32 humans, crossovers are repressed within (peri)centromeric regions. We previously 33 identified a key role for the multi-subunit, kinetochore-associated Ctf19 complex (Ctf19c; 34 the budding yeast equivalent of the human CCAN) in regulating pericentromeric crossover 35 formation. Here, we develop a dCas9/CRISPR-based system that allows ectopic targeting 36 of Ctf19c-subunits to a non-centromeric locus during meiosis. Using this approach, we 37 query sufficiency in meiotic crossover suppression, and identify Ctf19 (the budding yeast 38 homologue of vertebrate CENP-P) as a central mediator of kinetochore-associated 39 crossover control. We show that the effect of Ctf19 is encoded in its NH 2 -terminal tail, and 40 depends on residues known to be important for the recruitment of the Scc2-Scc4 cohesin 41 regulator to kinetochores. We thus reveal a crucial determinant that links kinetochores to 42 meiotic recombinational control. This work provides insight into localized control of 43 meiotic recombination. Furthermore, our approach establishes a dCas9/CRISPR-based 44 experimental platform that can be utilized to investigate and locally manipulate meiotic 45 crossover control. This platform can easily be adapted in order to investigate other aspects 46 of localized chromosome biology. 47 48 49 50 Introduction 51Faithful chromosome segregation in meiosis requires physical connections between 52 initially unpaired homologous chromosomes (Petronczki, et al., 2003). Such linkages are 53 established through homologous recombination (HR) mediated repair of programmed DNA 54 double strand breaks (DSBs) (Keeney, 2001). Sequences that can act as HR repair templates for 55 DSB lesions can be found on the sister chromatid and the homologous chromosome, but only 56 repair that uses the homologous chromosome as a template can result in the reciprocal exchange 57 of flanking chromosomal arm regions of homologous chromosomes, yielding a crossover. A 58 crossover, together with cohesin that is laid down distally to the recombination site, establishes 59 the connection between homologs required for successful chromosome segregation in meiosis. 60The placement of crossovers is determined by the location of DSB activity and by repair 61 decisions after DSB formation. Certain regions in the genome represent a high risk to genome 62 stability when faced with DSB repair or CO formation, and molecular systems are in place to 63 spatially control CO placement and thereby guard genomic stability during meiosis. 64 Centromeres are the regions of the chromosomes where kinetochores are nucleated. Kinetochores 65 a...