# S100PBP interacts with nucleoporin TPR and facilitates XY crossover formation in mice

## TL;DR

This study identifies S100PBP as a protein that helps form crossovers between X and Y chromosomes in mice and interacts with nuclear pore components during meiosis.

## Contribution

The study reveals S100PBP's dual role in promoting XY crossovers and limiting autosomal crossovers through its interaction with nucleoporin TPR.

## Key findings

- S100PBP is essential for XY crossover formation and male fertility in mice.
- S100PBP interacts with nucleoporin TPR and localizes to nuclear pores in meiocytes.
- Disruption of S100PBP increases autosomal recombination intermediates and crossovers.

## Abstract

During meiosis, at least one crossover is selectively generated per pair of homologous chromosomes through homologous recombination to ensure their faithful segregation. The molecular mechanisms controlling meiotic recombination, particularly in XY chromosomes that share a tiny region of homology (i.e., the pseudoautosomal region, PAR), remain poorly understood. Here, we identify S100PBP as a key modulator of both XY and autosomal recombination in mice. S100pbp-knockout mice exhibit male infertility and spermatogenesis arrest at meiotic metaphase I, resulting from a drastic reduction in XY crossovers. This failure in XY crossover formation is due to a reduction in TEX11/M1AP-bound recombination intermediates at the PAR. By contrast, disruption of S100PBP significantly increases the number of recombination intermediates and crossovers on autosomes. Co-immunoprecipitation mass spectrometry revealed that S100PBP interacts with the nucleoporin TPR. Furthermore, S100PBP is localized specifically to the nuclear pores of meiocytes, likely in a TPR-dependent manner. These findings demonstrate that S100PBP promotes XY crossover formation while limiting excess autosomal crossovers and shed light on the potential role of nuclear pores in regulating meiotic recombination.

This study shows that S100PBP interacts with the nucleoporin TPR and regulates meiotic crossover in mice, suggesting potential regulatory roles of nuclear pores in mammalian meiotic recombination.

S100PBP is essential for male fertility in mice.S100PBP facilitates XY crossover formation by promoting the formation and stability of TEX11/M1AP-bound recombination intermediates at the pseudoautosomal region (PAR).Depletion of S100PBP increases the numbers of TEX11/M1AP-bound recombination intermediates and crossovers on autosomes.In oocytes, S100PBP restricts excess crossover formation while being dispensable for follicle development and female fertility.S100PBP interacts with the nucleoporin TPR and is localized specifically to the nuclear pores of meiocytes in a TPR-dependent manner.

S100PBP is essential for male fertility in mice.

S100PBP facilitates XY crossover formation by promoting the formation and stability of TEX11/M1AP-bound recombination intermediates at the pseudoautosomal region (PAR).

Depletion of S100PBP increases the numbers of TEX11/M1AP-bound recombination intermediates and crossovers on autosomes.

In oocytes, S100PBP restricts excess crossover formation while being dispensable for follicle development and female fertility.

S100PBP interacts with the nucleoporin TPR and is localized specifically to the nuclear pores of meiocytes in a TPR-dependent manner.

This study shows that S100PBP interacts with the nucleoporin TPR and regulates meiotic crossover in mice, suggesting potential regulatory roles of nuclear pores in mammalian meiotic recombination.