Transcriptomic Analysis Reveals AKT1 Upregulation in Inner Mongolian Cashmere Goats at 12 and 15 Months of Age.

Cashmere production declines with age in Inner Mongolian cashmere goats, but the molecular mechanisms are unknown. This study employed a transcriptome-wide RNA-seq analysis to compare age-associated and breed-related gene expression profiles in goat skin, with particular emphasis on age-dependent AKT1 expression and its associated signaling pathways. Skin tissues from cashmere goats at 12 and 15 months and age-matched non-cashmere controls were analyzed by RNA-seq (BGIDNBSEQ platform). Differential expression and functional enrichment analyses were performed on skin transcriptomes of cashmere and control goats at 12 and 15 months. Age-specific functional profiles emerged: 12-month cashmere goats showed enrichment in GTPase activity, glucose transport, and ribosomal assembly, whereas 15-month goats were enriched for autophagosome assembly and apoptosis. FoxO signaling was commonly enriched across both ages, while the Hepatitis B pathway was unique to 12 months. AKT1 was significantly upregulated at 12 months coinciding with peak cashmere production with reduced expression at 15 months. This age-dependent pattern was supported by coordinated regulation of downstream effectors, including TSC2, PIK3R2, MAPK9, and FOXO3. Collectively, these transcriptomic data provide a mechanistic framework linking age-dependent AKT1 regulation to the decline in cashmere fiber production.