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bioRxiv · 10.1101/2024.08.07.607092

The synaptonemal complex assembles between meiotic chromosomes by wetting

Gordon, S.·Lee, C. F.·Rog, O.
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Abstract

AbstractDuring meiosis, the parental chromosomes are drawn together to enable exchange of genetic information. Chromosomes are aligned through the assembly of a conserved interface, the synaptonemal complex, composed of a central region that forms between two parallel chromosomal backbones called axes. Here we identify the axis-central region interface in C. elegans, containing a conserved positive patch on the axis component HIM-3 and the C-terminus of the central region protein SYP-5. Crucially, the canonical ultrastructure of the synaptonemal complex is altered upon weakening this interface. We developed a thermodynamic model that recapitulates our experimental observations, indicating that the liquid-like central region can assemble by wetting the axes without active energy consumption. More broadly, our data show that condensation drives tightly regulated nuclear reorganization during sexual reproduction.

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Gordon, S., Lee, C. F., Rog, O.. 2024-08-08. The synaptonemal complex assembles between meiotic chromosomes by wetting. https://doi.org/10.1101/2024.08.07.607092

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