Characterization of sheep spermatogenesis through single-cell RNA sequencing

Area of Science:

• Reproductive Biology
• Genomics
• Cellular Biology

Background:

• Spermatogenesis, essential for male reproduction, involves complex germ and somatic cell interactions.
• Cellular heterogeneity in testes complicates profiling distinct cell types and developmental stages.
• Understanding these interactions is vital for male reproductive health and fertility research.

Purpose of the Study:

• To conduct the first comprehensive, unbiased single-cell transcriptomic analysis of sheep spermatogenesis.
• To identify and characterize distinct germ and somatic cell types during sheep spermatogenesis.
• To discover stage-specific marker genes and enriched pathways in sheep testicular cells.

Main Methods:

• Utilized 10× genomics single-cell RNA sequencing (scRNA-seq) on adult sheep testis cells.
• Collected and analyzed scRNA-seq data from 11,772 individual cells.
• Performed functional enrichment analysis and identified stage-specific marker genes.

Main Results:

• Successfully identified all known germ cells (spermatocytes, spermatids, sperm) and somatic cells (Sertoli, Leydig), plus unexpected leukocytes.
• Functional enrichment analysis highlighted cell cycle, gamete generation, and protein processing pathways in germ cells, and ribosome pathways in somatic cells.
• Identified several stage-specific marker genes for sheep germ cells, including EZH2, SOX18, SCP2, PCNA, and PRKCD.

Conclusions:

• This research provides the first detailed transcriptional landscape of sheep spermatogenesis at the single-cell level.
• The findings offer novel insights into the molecular mechanisms governing sheep spermatogenic cell development and differentiation.
• The identified marker genes and pathways can serve as valuable targets for future studies in ovine reproduction and fertility.