Transcriptomic dynamics and cell-to-cell communication during the transition of prospermatogonia to spermatogonia revealed at single-cell resolution.

Background: Spermatogonia are essential for the continual production of sperm and regeneration of the entire spermatogenic lineage after injury. In mammals, spermatogonia are formed in the neonatal testis from prospermatogonia (also termed gonocytes), which are established from primordial germ cells during fetal development. Currently, the molecular regulation of the prospermatogonial to spermatogonia transition is not fully understood.

Elevated Id2 expression causes defective meiosis and spermatogenesis in mice.

Background: Inhibitors of DNA binding (ID) proteins mainly inhibit gene expression and regulate cell fate decisions by interacting with E-proteins. All four ID proteins (ID1-4) are present in the testis, and ID4 has a particularly important role in spermatogonial stem cell fate determination. Several lines of evidence indicate that ID proteins are involved in meiosis; however, functional experiments have not been conducted to validate this observation.

Transcription factor E4F1 dictates spermatogonial stem cell fate decisions by regulating mitochondrial functions and cell cycle progression.

Background: Spermatogonial stem cells (SSCs) provide a foundation for robust and continual spermatogenesis in mammals. SSCs self-renew to maintain a functional stem cell pool and differentiate to supply committed progenitors. Metabolism acts as a crucial determinant of stem cell fates; however, factors linking metabolic programs to SSC development and maintenance are poorly understood.

Long read genome assemblies complemented by single cell RNA-sequencing reveal genetic and cellular mechanisms underlying the adaptive evolution of yak.

Wild yak (Bos mutus) and domestic yak (Bos grunniens) are adapted to high altitude environment and have ecological, economic, and cultural significances on the Qinghai-Tibetan Plateau (QTP). Currently, the genetic and cellular bases underlying adaptations of yak to extreme conditions remains elusive. In the present study, we assembled two chromosome-level genomes, one each for wild yak and domestic yak, and screened structural variants (SVs) through the long-read data of yak and taurine cattle.

WTAP Function in Sertoli Cells Is Essential for Sustaining the Spermatogonial Stem Cell Niche.

Sertoli cells are the major component of the spermatogonial stem cell (SSC) niche; however, regulatory mechanisms in Sertoli cells that dictate SSC fate decisions remain largely unknown. Here we revealed features of the N-methyladenosine (mA) mRNA modification in Sertoli cells and demonstrated the functions of WTAP, the key subunit of the mA methyltransferase complex in spermatogenesis. mA-sequencing analysis identified 21,909 mA sites from 15,365 putative mA-enriched transcripts within 6,122 genes, including many Sertoli cell-specific genes.

E4 Transcription Factor 1 (E4F1) Regulates Sertoli Cell Proliferation and Fertility in Mice.

In the mammalian testes, Sertoli cells are the only somatic cells in the seminiferous tubules that provide structural, nutritional and regulatory support for developing spermatogenic cells. Sertoli cells only proliferate during the fetal and neonatal periods and enter a quiescent state after puberty. Functional evidences suggest that the size of Sertoli cell population determines sperm production and fertility.

Function and transcriptomic dynamics of Sertoli cells during prospermatogonia development in mouse testis.

In mammals, spermatogonial stem cells (SSCs) arise from a subpopulation of prospermatogonia during neonatal testis development. Currently, molecular mechanisms directing the prospermatogonia to spermatogonial transition are not well understood. In the study, we found that reducing Sertoli cells number by Amh-cre mediated expression of diphtheria toxin (AC;DTA) in murine fetal testis caused defects in prospermatogonia fate decisions.

Ring 1 and YY1 Binding Protein Expressed in Murine Spermatocytes but Dispensable for Spermatogenesis.

Spermatogenesis is a complex cellular-differentiation process that relies on the precise regulation of gene expression in spermatogonia, meiotic, and postmeiotic germ cells. The Ring 1 and YY1 binding protein (Rybp) is a member of the mammalian polycomb-group (PcG) protein family that plays multifunctional roles in development. Previous findings indicate that Rybp may function as an important regulator of meiosis.

Testosterone-retinoic acid signaling directs spermatogonial differentiation and seasonal spermatogenesis in the Plateau pika (Ochotona curzoniae).

During evolution, animals optimize their reproductive strategies to increase offspring survival. Seasonal breeders reproduce only during certain times of the year. In mammals, reproduction is tightly controlled by hypothalamus-pituitary-gonad axis.