Corporate Banner
Satellite Banner
Genomics
Scientific Community
 
Become a Member | Sign in
Home>News>This Article
  News
Return

Quality of Waking Hours Key to Falling Sleep

Published: Monday, July 15, 2013
Last Updated: Monday, July 15, 2013
Bookmark and Share
UT Southwestern researchers identifies two proteins never before linked to alertness and sleep-wake balance.

The quality of wakefulness affects how quickly a mammal falls asleep, UT Southwestern Medical Center researchers report in a study that identifies two proteins never before linked to alertness and sleep-wake balance.

“This study supports the idea that subjective sleepiness is influenced by the quality of experiences right before bedtime. Are you reluctantly awake or excited to be awake?” said Dr. Masashi Yanagisawa, professor of molecular genetics and a Howard Hughes Medical Institute investigator at UT Southwestern. He is principal author of the study published online in May in the Proceedings of the National Academy of Sciences.

Co-author Dr. Robert Greene, UT Southwestern professor of psychiatry and a physician at the Dallas VA Medical Center, said the study is unique in showing that the need for sleep (called sleep homeostasis) can be separated from wakefulness both behaviorally and biochemically, meaning the two processes can now be studied individually.

“Two of the great mysteries in neuroscience are why do we sleep and what is sleep’s function? Separating sleep need from wakefulness and identifying two different proteins involved in these steps represents a fundamental advance,” he said.

If borne out by further research, this study could lead to new ways of assessing and possibly treating sleep disorders, perhaps by focusing more attention on the hours before bedtime because the quality of wakefulness has a profound effect on sleep, Dr. Yanagisawa said.

The experiment featured three groups of mice with virtually identical genes. The control group slept and woke at will and followed the usual mouse pattern of sleeping during the day and being awake at night.

The two test groups were treated the same and had the same amount of sleep delay - six hours - but they were kept awake in different ways, said lead author Dr. Ayako Suzuki, a postdoctoral researcher who works in the laboratories of both Dr. Yanagisawa and Dr. Greene.

The first test group’s sleep was delayed by a series of cage changes. Mice are intensely curious, so each cage change was followed by an hour spent vigorously exploring the new surroundings.

This behavior would roughly correspond to teenagers voluntarily delaying bedtime with a new and stimulating event like a rock concert or video game.

Researchers kept the second group awake as gently as possible, usually by waving a hand in front of the cage or tapping it lightly whenever the mice appeared to be settling down to sleep. That test group would more resemble parents reluctantly staying awake awaiting a child’s return from a concert.

Both test groups experienced the same amount of sleep deprivation, but their reactions to the different forms of alertness were striking, Dr. Yanagisawa said. In one test, the cage-changing group took longer to fall asleep than the gentle-handling group even though an analysis of their brain waves indicated equal amounts of sleep need in both test groups.

“The need to sleep is as high in the cage-changing group as in the gentle-handling group, but the cage-changers didn’t feel sleepy at all. Their time to fall asleep was nearly the same as the free-sleeping, well-rested control group,” he said.

The researchers identified two proteins that affected these responses, each linked to different aspects of sleep: phosphorylated dynamin 1 levels were linked to how long it took to fall asleep, while phosphorylated N-myc downstream regulated gene 2 protein levels tracked the amount of sleep deprivation and corresponded to the well-known brain-wave measure of sleep need, they report.

“The two situations are different biochemically, which is a novel finding,” Dr. Yanagisawa said, adding, “These proteins are completely new to sleep research and have never before been linked to sleep need and wakefulness.”

From an evolutionary perspective, an arousal mechanism that adapts to environmental stimuli is crucial because sleeping on a rigid schedule could be dangerous. “Animals, including humans, must be able to keep themselves at least temporarily alert, say during a natural disaster,” he said.

Drs. Yanagisawa and Greene are both corresponding authors on the study, and both have dual appointments at the International Institute for Integrative Sleep Medicine, University of Tsukuba, Tsukuba, Japan. Former Associate Professor of Internal Medicine Dr. Christopher M. Sinton, now at the University of Arizona, was also involved in the study.

The study was funded by the Japan Society for the Promotion of Science through the Funding Program for World-Leading Innovative R&D on Science and Technology; the Perot Family Foundation; and the Department of Veterans Affairs.


Further Information
Access to this exclusive content is for Technology Networks Premium members only.

Join Technology Networks Premium for free access to:

  • Exclusive articles
  • Presentations from international conferences
  • Over 2,500+ scientific posters on ePosters
  • More than 3,800+ scientific videos on LabTube
  • 35 community eNewsletters


Sign In



Forgotten your details? Click Here
If you are not a member you can join here

*Please note: By logging into TechnologyNetworks.com you agree to accept the use of cookies. To find out more about the cookies we use and how to delete them, see our privacy policy.

Related Content

Cell that Replenishes Heart Muscle Found by UT Southwestern Researchers
Researchers devise a new cell-tracing technique to detect cells that do replenish themselves.
Tuesday, June 23, 2015
Researchers Find Molecular Mechanisms within Fetal Lungs that Initiate Labor
Biochemists found that steroid receptor coactivators 1 and 2 (SRC-1 and SRC-2) proteins control genes.
Tuesday, June 23, 2015
Researchers Discover Molecule that Accelerates Tissue Regeneration
Newly discovered molecule, SW033291 accelerate cell recovery following bone marrow transplants.
Friday, June 12, 2015
Mutations in Two Genes Linked to Familial Pulmonary Fibrosis and Telomere Shortening
PARN and RTEL1 genes strengthen the link between lung fibrosis and telomere dysfunction.
Tuesday, May 05, 2015
Scientists Identify Key Receptors Behind Development of AML
Blocking ITIM-receptor signaling in combination with conventional therapies may represent a novel strategy for AML treatment.
Saturday, May 02, 2015
Study Reveals Molecular Genetic Mechanisms Driving Breast Cancer Progression
The findings are published online and in the journal Molecular Cell.
Saturday, April 04, 2015
New Cyclotron Facility at UT Southwestern
Expands research opportunities and imaging capabilities for detecting, tracking cancer.
Friday, March 20, 2015
Acetate Supplements Shown to Speed Up Cancer Growth
A major compound produced in the gut by host bacteria.
Friday, February 20, 2015
MAGE Genes Provide Insight into Optimizing Chemotherapy
UT Southwestern Medical Center scientists have identified a new biomarker that could help identify patients who are more likely to respond to certain chemotherapies.
Tuesday, February 17, 2015
Researchers Identify ‘Achilles heel’ in Metabolic Pathway
Achilles heel could lead to new lung cancer treatments.
Saturday, February 14, 2015
Study Links Deficiency of Cellular Housekeeping Gene with Aggressive Forms of Breast Cancer
Research team studies genes involved in the autophagy process and their roles in cancer, aging, infections, and neurodegenerative diseases.
Saturday, January 31, 2015
Targeting The Cell’s ‘Biological Clock’
Researchers target the cell’s ‘biological clock’ in promising new therapy to kill cancer cells, shrink tumor growth.
Monday, January 05, 2015
Whole-Genome Sequencing Successfully Identifies Cancer-Related Mutations
UT Southwestern Medical Center cancer researchers have demonstrated that whole-genome sequencing can be used to identify patients’ risk for hereditary cancer.
Wednesday, December 24, 2014
Therapeutic Strategy May Treat a Childhood Neurological Disorder
Researchers have identified a possible therapy to treat neurofibromatosis type 1 or NF1.
Wednesday, December 17, 2014
Signaling Mechanism Could Be Target For Survival, Growth Of Tumor Cells In Brain Cancer
Non-canonical EGFR signalling shown to make glioblastoma tumor cells more resistant to chemotherapy treatment.
Monday, December 15, 2014
Scientific News
Poor Survival Rates in Leukemia Linked to Persistent Genetic Mutations
For patients with an often-deadly form of leukemia, new research suggests that lingering cancer-related mutations – detected after initial treatment with chemotherapy – are associated with an increased risk of relapse and poor survival.
Searching Big Data Faster
Theoretical analysis could expand applications of accelerated searching in biology, other fields.
Growing Hepatitis C in the Lab
Recent discovery allows study of naturally occurring forms of hepatitis C virus (HCV) in the lab.
Inciting an Immune Attack on Cancer Cells
A new minimally invasive vaccine that combines cancer cells and immune-enhancing factors could be used clinically to launch a destructive attack on tumors.
Reprogramming Cancer Cells
Researchers on Mayo Clinic’s Florida campus have discovered a way to potentially reprogram cancer cells back to normalcy.
Genetic Overlapping in Multiple Autoimmune Diseases May Suggest Common Therapies
CHOP genomics expert leads analysis of genetic architecture, with eye on repurposing existing drugs.
Surprising Mechanism Behind Antibiotic-Resistant Bacteria Uncovered
Now, scientists at TSRI have discovered that the important human pathogen Staphylococcus aureus, develops resistance to this drug by “switching on” a previously uncharacterized set of genes.
How DNA ‘Proofreader’ Proteins Pick and Edit Their Reading Material
Researchers from North Carolina State University and the University of North Carolina at Chapel Hill have discovered how two important proofreader proteins know where to look for errors during DNA replication and how they work together to signal the body’s repair mechanism.
Fat in the Family?
Study could lead to therapeutics that boost metabolism.
Tissue Bank Pays Dividends for Brain Cancer Research
Checking what’s in the bank – the Brisbane Breast Bank, that is – has paid dividends for UQ cancer researchers.
Skyscraper Banner

Skyscraper Banner
Go to LabTube
Go to eposters
 
Access to the latest scientific news
Exclusive articles
Upload and share your posters on ePosters
Latest presentations and webinars
View a library of 1,800+ scientific and medical posters
2,500+ scientific and medical posters
A library of 2,500+ scientific videos on LabTube
3,800+ scientific videos
Close
Premium CrownJOIN TECHNOLOGY NETWORKS PREMIUM FREE!