SCN tagged posts

In this slice of the master clock, cells expressing an astrocyte-specific structural protein that had been stained red (top right panel) matched up well with cells that had been equipped to fluoresce green when they were expressing a clock gene (middle right panel), demonstrating that the scientists could watch astrocytes tick in the clock. Credit: Herzog Lab

Until recently, work on biological clocks that dictate daily fluctuations in most body functions, including core body temperature and alertness, focused on neurons, those electrically excitable cells that are the divas of the central nervous system. Asked to define the body’s master clock, biologists would say it is the suprachiasmatic nuclei, or SCN – in the brain that consist of 20,000 neurons...

Before the delivery of the neurotoxin (left) the SCN oscillate in a synchronized pattern. After the delivery of the neurotoxin (right), neurons in the SCN oscillate randomly. Credit: Image courtesy of the Doyle Lab

For the 1st time it has been shown how neurons in the SCN are connected to each other, shedding light on this vital area of the brain. Understanding this structure – and how it responds to disruption – is important for tackling illnesses like diabetes and PTSD. The scientists have also found that disruption to these rhythms such as shifts in work schedules or blue light exposure at night can negatively impact overall health...