Multivalent weak interactions between assembly units drive synaptonemal complex formation

J Cell Biol. 2020 May 4;219(5):e201910086. doi: 10.1083/jcb.201910086.


The synaptonemal complex (SC) is an ordered but highly dynamic structure assembled between homologous chromosomes to control interhomologous crossover formation, ensuring accurate meiotic chromosome segregation. However, the mechanisms regulating SC assembly and dynamics remain unclear. Here, we identified two new SC components, SYP-5 and SYP-6, in Caenorhabditis elegans that have distinct expression patterns and form distinct SC assembly units with other SYPs through stable interactions. SYP-5 and SYP-6 exhibit diverse in vivo SC regulatory functions and distinct phase separation properties in cells. Charge-interacting elements (CIEs) are enriched in SC intrinsically disordered regions (IDRs), and IDR deletion or CIE removal confirmed a requirement for these elements in SC regulation. Our data support the theory that multivalent weak interactions between the SC units drive SC formation and that CIEs confer multivalency to the assembly units.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Caenorhabditis elegans / genetics*
  • Caenorhabditis elegans Proteins / genetics*
  • Chromosome Pairing / genetics
  • Chromosome Segregation / genetics*
  • Meiosis / genetics
  • Nuclear Proteins / genetics
  • Synaptonemal Complex / genetics*


  • Caenorhabditis elegans Proteins
  • Nuclear Proteins