# Rnf32 is not essential for spermatogenesis and male fertility in mice

## TL;DR

This study shows that Rnf32 is not essential for sperm production or male fertility in mice, despite being active during sperm development.

## Contribution

The study demonstrates that Rnf32 knockout mice remain fertile, challenging its assumed role in male reproduction.

## Key findings

- Male Rnf32−/− mice showed normal fertility and sperm parameters.
- Testicular and epididymal histology and spermatogenesis were unaffected in Rnf32 knockout mice.
- Rnf32 is not essential for male fertility in mice.

## Abstract

Ring finger motifs are found in a variety of proteins with diverse functions, often involved in protein-DNA or protein–protein interactions. The Rnf32-encoded protein contains two such motifs and is predominantly expressed in the testes and ovaries, suggesting that its expression may be regulated by elements within the Rnf32 promoter region. Rnf32 is active during spermatogenesis, mainly in spermatocytes and spermatids, indicating a potential role in sperm development.

We established an Rnf32 knockout (Rnf32−/−) mouse model using CRISPR/Cas9 technology. Gene expression was analyzed via reverse transcription quantitative polymerase chain reaction (RT-qPCR). Testicular and epididymal phenotypes were assessed through histological and immunofluorescence staining, and fertility and sperm motility were evaluated.

Here, we successfully established an Rnf32 knockout mouse model using CRISPR/Cas9 technology. Surprisingly, male Rnf32−/− mice exhibited normal fertility, with no significant differences in testicular and epididymal histology, spermatogenesis, sperm count, or motility compared to Rnf32+/+ mice. These findings suggest that Rnf32 may not be essential for male fertility in mice, and its potential functions warrant further investigation.