Fig. 2

Enactment of the reproductive dramas by the HPG axis via a set of key parameters and small molecules. As each parameter is controlled by a labyrinth of sensing and effecting systems, so is every molecule intricately enmeshed in a network of pathways. These biophysical parameters and biological molecules have coalesced into the bedrock of cellular life through billions years of evolution. DNMT/TET is used to represent the epigenetic regulatory machinery and even microRNAs which are closely interconnected with the machinery. T temperature, p02 partial pressure of oxygen, pH power of hydrogen or potential of hydrogen, N/E nutrient/energy, p53 phosphoprotein 53, HIF hypoxia inducible factor, MYC transcription factor of myelocytomatosis viral oncogene homolog, HO-1 heme oxygenase-1, HLA-G human leucocyte antigen-G, DNMT/TET DNA methyltransferase/ten-eleven translocation methylcytosine dioxygenase, EMT/MET epithelial–mesenchymal transition/mesenchymal–epithelial transition