SUN-242 Transcriptome of the Amygdala in Normal Cyclic and Acyclic Gilts

Many replacement gilts fail to express estrus, which results from being nonpubertal or behavioral anestrus. Genomic studies identified neuronal and olfaction pathways associated with these reproductive phenotypes. To better understand puberty failure, the transcriptome of the amygdala in nonpubertal, behavioral anestrus and normal cyclic gilts in the early follicular and midluteal phase was evaluated (n = 8/group; mean age = 259 d). An average of 57 million reads were obtained from each of 32 TruSeq mRNA libraries and mapped to Sscrofa 11.1. Differential expression of genes (DEG; adjusted P < 0.05) was determined using DESeq2 and pathway analysis performed with iPathwayGuide. A total of 17,173 annotated genes were expressed (raw read count > 15 in ≥ 8 samples). Comparing amygdala expression in nonpubertal gilts with follicular phase control gilts revealed 6 DEG (3 unannotated) including ARRDC2, ZFAND2A, and LAMC2. The only DEG identified between behavioral anestrus gilts and luteal phase control gilts was PIK3CG. There were 88 DEG in the amygdala of follicular phase gilts compared with luteal phase gilts. Expression of 73 genes was upregulated in the amygdala of follicular phase gilts and 14 genes were more highly expressed in luteal phase gilts. Enriched pathways included TGFβ signaling and ion transport related to GABAergic and glutamatergic neuronal function. Molecular processes for chemokine binding, membrane transporters and receptor signaling through phosphatidylinositol and tyrosine kinases were upregulated in the amygdala of follicular phase gilts. Prominent cellular components included ion channels and integrins necessary for focal adhesions that promote dendritic growth and neuronal synapse. Major differences in the amygdala of prepubertal and behavioral anestrus gilts were not found, with few genes differentially expressed compared to cyclic gilts. Stage of the ovarian cycle majorly impacted gene expression related to increased neuronal activity in the amygdala of follicular phase gilts. USDA is an equal opportunity provider and employer.