Key Genetic Triggers in Weight Regulating Brain Cells Found

In a recent study published in the journal PLoS Genetics, a team of researchers from the University of Michigan found that the “little voice” inside our heads that tells us to eat, or stop eating, is comprised of about 10,000 specialized brain cells, and there are tiny triggers inside those cells that give rise to this “voice.” The neurons, called POMC cells, are located inside the hypothalamus, and act as a control center for feelings of fullness or hunger, and they take in signals from the body, sending out chemical signals to regulate appetite. When POMC neurons are absent, or not working correctly, humans grow dangerously obese. The results of the study found that in animals, when certain genetic triggers inside the POMC cells aren’t working, the same thing happens. During the study, researchers also reported on a protein called a transcription factor, and two small stretches of DNA, called enhancers, which act as triggers for the POMC gene. All three regulate how often, and when, the POMC cells use the gene to create the signal molecules that then go out to the body. The transcription factor, called Islet 1, also plays a key role in helping POMC cells form correctly during the earliest stages of the brain’s development, before birth. The discovery shows the impact of two different gene enhancers — stretches of DNA near the POMC gene that make it easier for the cell to read it. Like signal lights that show pilots the path to an airport runway, enhancers guide proteins toward the gene so it can be read. The researchers found that the two enhancers act in ways that complement one another, both encouraging the expression of the POMC gene at key times. To read more about this study, click here.