According to the paper, which was published in the journal Nature Neuroscience, the OHSU investigators are researching how the control of puberty is affected by epigenetics, which are changes in gene activity linked to external factors that do not involve changes to the genetic code itself. By improving the understanding of these complex protein/gene interactions, the OHSU scientists believe they will be better able to understand both early-onset (precocious) puberty and delayed puberty, and highlight new therapy avenues.
For their study, researchers examined puberty in female rats, finding that a group of proteins, called PcG proteins, regulate the activity of a gene called the Kiss1 gene. Your body needs the Kiss1 gene for puberty to occur, and when these PcG proteins diminish, your Kiss1 is activated and puberty begins. The role of PcG proteins is to turn off specific downstream genes at key developmental stages.
According to the OHSU scientists, two forms of epigenetic control impact the activity of these ‘master’ genes and their ability to turn off puberty. The first is a chemical modification of DNA known as DNA methylation, and the other is changes in the composition of a specialised set of proteins, known as histones, that modify your gene activity by interacting with DNA.
The researchers were able to use this information to delay the early-onset of puberty in female rats, and their work is a first because, as Alejandro Lomniczi, PhD, a scientist in the Division of Neuroscience at the OHSU Oregon National Primate Research Centre, explained, ‘While it was always understood that an organism’s genes determine the timing of puberty, the role of epigenetics in this process has never been recorded until now.’
Sergio Ojeda, DVM, who is also a scientist in the Division of Neuroscience at the OHSU ONPRC, commented, ‘Because epigenetic changes are driven by environmental, metabolic and cell-to-cell influences, these findings raise the possibility that a significant percentage of precocious and delayed puberty cases occurring in humans may be the result of environmental factors and other alterations in epigenetic control.’ She added, ‘There is also much more to be learned about the way that epigenetic factors may link environmental factors such as nutrition, man-made chemicals, social interactions and other day-today influences to the timing and completion of normal puberty.’