A defining feature of meiosis is the synaptonemal complex (SC), a zipper-like protein structure that forms between homologous chromosomes to regulate their recombination and segregation. Historically viewed as an enigmatic electron-dense scaffold, the SC is now recognized as a dynamic signaling platform that coordinates key meiotic processes. Here, we review recent advances in understanding SC structure and function. We describe diverse complementary approaches that have expanded the catalog of SC components and their network of interactions within this architecture. We highlight striking conservation in structural organization and ancient molecular modules that couple SC structure to crossover regulation and further discuss how the SC implements feedback mechanisms controlling meiotic DNA break formation and repair capacity to ensure faithful chromosome segregation across generations.
© 2026 Cesar and Kim.