Ribosome profiling sequencing reveals translational dynamics during yak testicular development

Translation regulation plays a crucial role in testicular development and spermatogenesis, but its dynamic mechanism has not yet been elucidated. This study integrated transcriptome data through ribosomal sequencing (Ribo-seq) to analyze the translation landscape of yak (Bos grunniens) testes at 6 months (Y6M), 18 months (Y18M), and 4 years (Y4Y) of age. The results revealed that the ribosome footprint characteristics of yaks were consistent with those of other mammals. The differentially translated genes during sexual maturity are significantly enriched in the meiotic cell cycle, PI3K Akt, and Notch signaling pathways. From Y6M to Y18M, most of the TE altered genes showed inverse transcription-translation efficiency trends, potentially involved in protein ubiquitination modification. From 18 M to 4Y, translationally altered genes lacked transcriptional changes but associated with acetyltransferase and phosphotransferase activity. PPI analysis identified stage-specific regulatory genes: COL1A2/MEIOB/SYCP3 (6 M–18 M) and STAT1/ITGB5/ERBB2 (18 M-4Y). Additionally, we identified 106 predicted translatable small open reading frames (sORFs), which included annotations for 58 known coding proteins and 1 long non-coding RNA. Sequence feature analysis revealed that higher translation efficiency correlates with longer uORF length, lower GC content, shorter CDS length, and higher NMEF. In conclusion, the results provide new insights into the dynamic regulation of gene translation during testicular development and spermatogenesis, which is highly significant for enhancing yak reproductive performance.