Transcription factor Dmrt1 triggers the SPRY1-NF-κB pathway to maintain testicular immune homeostasis and male fertility

Bacterial or viral infections,such as Brucella,mumps virus,herpes simplex virus,and Zika virus,destroy immune homeostasis of the testes,leading to spermatogenesis disorder and infertility.Of note,recent research shows that SARS-CoV-2 can infect male gonads and destroy Sertoli and Leydig cells,leading to male reproductive dysfunction.Due to the many side effects associated with antibiotic therapy,finding alternative treatments for inflammatory injury remains critical.Here,we found that Dmrt1 plays an important role in regulating testicular immune homeostasis.Knockdown of Dmrt1 in male mice inhibited spermatogenesis with a broad inflammatory response in seminiferous tubules and led to the loss of spermatogenic epithelial cells.Chromatin immunoprecipitation sequencing(ChIP-seq)and RNA sequencing(RNA-seq)revealed that Dmrt1 positively regulated the expression of Spry1,an inhibitory protein of the receptor tyrosine kinase(RTK)signaling pathway.Furthermore,immunoprecipitation-mass spectrometry(IP-MS)and co-immunoprecipitation(Co-IP)analysis indicated that SPRY1 binds to nuclear factor kappa B1(NF-κB1)to prevent nuclear translocation of p65,inhibit activation of NF-κB signaling,prevent excessive inflammatory reaction in the testis,and protect the integrity of the blood-testis barrier.In view of this newly identified Dmrt1-Spry1-NF-κB axis mechanism in the regulation of testicular immune homeostasis,our study opens new avenues for the prevention and treatment of male reproductive diseases in humans and livestock.

Single-cell RNA sequencing reveals atlas of dairy goat testis cells

Single-cell RNA sequencing(scRNA-seq)is useful for exploring cell heterogeneity.For large animals,however,little is known regarding spermatogonial stem cell(SSC)selfrenewal regulation,especially in dairy goats.In this study,we described a high-resolution scRNA-seq atlas derived from a dairy goat.We identified six somatic cell and five spermatogenic cell subtypes.During spermatogenesis,genes with significantly changed expression were mainly enriched in the Notch,TGF-β,and Hippo signaling pathways as well as the signaling pathway involved in the regulation of stem cell pluripotency.We detected and screened specific candidate marker genes(TKTL1 and AES)for spermatogonia.Our study provides new insights into goat spermatogenesis and the development of testicular somatic cells.

Dmrt1 regulates the immune response by repressing the TLR4 signaling pathway in goat male germline stem cells

Double sex and mab-3-related transcription factor 1(Dmrt1),which is expressed in goat male germline stem cells(mGSCs)and Sertoli cells,is one of the most conserved transcription factors involved in sex determination.In this study,we highlighted the role of Dmrt1 in balancing the innate immune response in goat mGSCs.Dmrt1 recruited promyelocytic leukemia zinc finger(Plzf),also known as zinc finger and BTB domain-containing protein 16(Zbtb16),to repress the Toll-like receptor 4(TLR4)-dependent inflammatory signaling pathway and nuclear factor(NF)-κB.Knockdown of Dmrt1 in seminiferous tubules resulted in widespread degeneration of germ and somatic cells,while the expression of proinflammatory factors were significantly enhanced.We also demonstrated that Dmrt1 stimulated proliferation of mGSCs,but repressed apoptosis caused by the immune response.Thus,Dmrt1 is sufficient to reduce inflammation in the testes,thereby establishing the stability of spermatogenesis and the testicular microenvironment.