During meiosis, crossing over allows for the exchange of genes
between homologous chromosomes, enabling their segregation
and leading to genetic variation in the resulting gametes.
Spo11, a topoisomerase-like protein expressed in eukaryotes,
and diverse accessory factors induce programmed doublestrand
breaks (DSBs) to initiate meiotic recombination during
the early phase of meiosis after DNA replication. DSBs
are further repaired via meiosis-specific homologous recombination.
Studies on budding yeast have provided insights
into meiosis and genetic recombination and have improved
our understanding of higher eukaryotic systems. Cohesin, a
chromosome-associated multiprotein complex, mediates sister
chromatid cohesion (SCC), and is conserved from yeast
to humans. Diverse cohesin subunits in budding yeast have
been identified in DNA metabolic pathways, such as DNA
replication, chromosome segregation, recombination, DNA
repair, and gene regulation. During cell cycle, SCC is established
by multiple cohesin subunits, which physically bind
sister chromatids together and modulate proteins that involve
in the capturing and separation of sister chromatids. Cohesin
components include at least four core subunits that establish
and maintain SCC: two structural maintenance chromosome
subunits (Smc1 and Smc3), an α-kleisin subunit (Mcd1/Scc1
during mitosis and Rec8 during meiosis), and Scc3/Irr1 (SA1
and SA2). In addition, the cohesin-associated factors Pds5
and Rad61 regulate structural modifications and cell cyclespecific
dynamics of chromatin to ensure accurate chromosome
segregation. In this review, we discuss SCC and the
recombination pathway, as well as the relationship between
the two processes in budding yeast, and we suggest a possible
conserved mechanism for meiotic chromosome dynamics
from yeast to humans.