Whole-Transcriptome Sequencing and Differential Expression Analysis of the Epididymis in Junggar Bactrian Camels Before and After Sexual Maturity.

The Junggar Bactrian camel, a primitive indigenous breed in China, exhibits low reproductive efficiency under natural grazing conditions. This is partly attributed to the development of the epididymis and the quality of semen, both of which directly affect reproductive performance. The epididymis is a key male reproductive organ responsible for sperm storage and transport. However, the gene expression profile of camel epididymal tissue remains poorly understood. In this study, we conducted whole-transcriptome sequencing of epididymal tissues from Junggar Bactrian camels before and after sexual maturity. A total of 683 differentially expressed mRNAs (DEmRNAs) were identified, including , , , and , of which 415 were upregulated and 268 were downregulated. Additionally, 260 differentially expressed long non-coding RNAs (DELncRNAs), including , , and , were identified, with 113 upregulated and 147 downregulated. An additional 11 differentially expressed microRNAs (DEmiRNAs), including and , were also detected. Gene Ontology (GO) annotation and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses revealed that key differentially expressed genes (DEGs), including , , , , and , were mainly involved in pathways such as Cell Adhesion Molecules, Phospholipase D signaling, Cytokine-Cytokine Receptor Interaction, and Olfactory Transduction. This study presents a comprehensive whole-transcriptome analysis of the epididymis in Junggar Bactrian camels before and after sexual maturity, identifying key genes and regulatory pathways associated with epididymal development and reproductive function. These findings provide a theoretical foundation and valuable data for future research on reproductive performance and epididymal biology in Bactrian camels.