Figure 2.
Mechanisms of GnRH secretion in the hypothalamus: insights from positional candidate genes identified in the meta-analyses of heifer fertility traits. Figure includes interaction of neurotransmitters from glutamatergic, GABAergic, cholinergic and Kisspeptin neurons with their respective receptors to excite GnRH neurons through calcium and cAMP signaling for GnRH secretion. Proteins in green represent the positional candidate genes, within 0.5 Mb of significant SNPs, which are also known in these KEGG pathways. Blue proteins represent the positional candidate genes placed in these intricate mechanisms based on the literature (but are not known from KEGG pathways). Grey proteins were not represented in the positional candidate gene list, but are components of the proposed mechanism due to current literature [6,10,47,48,49,50,51,52,53,54,55,56,57,58,59,60,61,62,63,64,65,66,67] and KEGG pathways. Red stars identify proteins from this study in common with previous proteomics and transcriptomics analyses of pre- vs post-pubertal heifers.