Fruitfly Study Identifies Brain Circuit that Drives Daily Cycles of Rest and Activity
Read the full article Fruitfly Study Identifies Brain Circuit that Drives Daily Cycles of Rest and Activity at NeuroscienceNews.com.
Amita Sehgal, PhD, a professor of Neuroscience at the Perelman School of Medicine, University of Pennsylvania, describes in Cell a circuit in the brain of fruit flies that controls their daily, rhythmic behavior of rest and activity. The new study also found that the fly version of the human brain protein known as corticotrophin releasing factor (CRF) is a major coordinating molecule in this circuit. Fly CRF, called DH44, is required for rest/activity cycles and is produced in cells that receive input from the clock cells in the fly brain. In mammals, CRF is secreted rhythmically and it drives the expression of glucocorticoids such as cortisol and is associated with stress and anxiety.
The research is in Cell. (full access paywall)
Research: “Identification of a Circadian Output Circuit for Rest:Activity Rhythms in Drosophila” by Daniel J. Cavanaugh, Jill D. Geratowski, Julian R.A. Wooltorton, Jennifer M. Spaethling, Clare E. Hector, Xiangzhong Zheng, Erik C. Johnson, James H. Eberwine, Amita Sehgal in Cell. doi:10.1016/j.cell.2014.02.024
Image: Model of the circadian output circuit for locomotor rhythms. One hemisphere of the fly brain is depicted. The circuit extends from the master pacemaker cells called s-LNvs (red), through other cells called DN1s (orange), and on to different types of pars intercerebralis cells (blue), which modulate locomotor rhythms through the release of the molecule DH44. Credit Daniel Cavanaugh.
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