Menu
The world of science and progress
Pulsar Transformed Into Small Planet Made of Diamond Discovered in Milky Way

New Depiction of Light Could Boost Telecommunications Channels

Free Radicals Crucial to Suppressing Appetite

Preserving 4 Percent of the Ocean Could Protect Most Marine Mammal Species, Study Finds

Panda Poop May Be a Treasure Trove of Microbes for Making Biofuels

Discovery Sheds Light On the Ecosystem of Young Galaxies

New Method Reveals Parts of Bacterial Genome Essential to Life

Novel Alloy Could Produce Hydrogen Fuel from Sunlight

Tiny Oxygen Generators Boost Effectiveness of Anticancer Treatment

Bedrock Nitrogen May Help Forests Buffer Climate Change, Study Finds

'Gene Overdose' Causes Extreme Thinness

Manufacturing Method Paves Way for Commercially Viable Quantum Dot-Based LEDs

Cutting Soot Emissions: Fastest, Most Economical Way to Slow Global Warming?

Tasmanian Tiger's Jaw Was Too Small to Attack Sheep, Study Shows

Manipulating Plants' Circadian Clock May Make All-Season Crops Possible

NASA's Chandra Finds Nearest Pair of Supermassive Black Holes

Up from the Depths: How Bacteria Capture Carbon in the 'Twilight Zone'

Understanding Next-Generation Electronic Devices: Smallest Atomic Displacements Ever

Woolly Rhino Fossil Discovery in Tibet Provides Important Clues to Evolution of Ice Age Giants

Sparing or Sharing? Protecting Wild Species May Require Growing More Food On Less Land

Glowing, Blinking Bacteria Reveal How Cells Synchronize Biological Clocks

Rock Rafts Could Be 'Cradle of Life'

Robots Learn to Handle Objects, Understand New Places

World's Smallest Electric Motor Made from a Single Molecule

First Stem Cells from Endangered Species

Glowing, Blinking Bacteria Reveal How Cells Synchronize Biological Clocks
Biologists have long known that organisms from bacteria to humans use the 24 hour cycle of light and darkness to set their biological clocks. But exactly how these clocks are synchronized at the molecular level to perform the interactions within a population of cells that depend on the precise timing of circadian rhythms is less well understood.

To better understand that process, biologists and bioengineers at UC San Diego created a model biological system consisting of glowing, blinking E. coli bacteria. This simple circadian system, the researchers report in the September 2 issue of Science, allowed them to study in detail how a population of cells synchronizes their biological clocks and enabled the researchers for the first time to describe this process mathematically.

"The cells in our bodies are entrained, or synchronized, by light and would drift out of phase if not for sunlight," said Jeff Hasty, a professor of biology and bioengineering at UC San Diego who headed the research team. "But understanding the phenomenon of entrainment has been difficult because it's difficult to make measurements. The dynamics of the process involve many components and it's tricky to precisely characterize how it works. Synthetic biology provides an excellent tool for reducing the complexity of such systems in order to quantitatively understand them from the ground up. It's reductionism at its finest."

To study the process of entrainment at the genetic level, Hasty and his team of researchers at UC San Diego's Biocircuits Institute combined techniques from synthetic biology, microfluidic technology and computational modeling to build a microfluidic chip with a series of chambers containing populations of E. coli bacteria. Within each bacterium, the genetic machinery responsible for the biological clock oscillations was tied to green fluorescent protein, which caused the bacteria to periodically fluoresce.

To simulate day and night cycles, the researchers modified the bacteria to glow and blink whenever arabinose -- a chemical that triggered the oscillatory clock mechanisms of the bacteria -- was flushed through the microfluidic chip. In this way, the scientists were able to simulate periodic day-night cycles over a period of only minutes instead of days to better understand how a population of cells synchronizes its biological clocks.

Hasty said a similar microfluidic system in principal could be constructed with mammalian cells to study how human cells synchronize with light and darkness. Such genetic model systems would have important future applications since scientists have discovered that problems with the biological clock can result in many common medical problems from diabetes to sleep disorders.

Other members of Hasty's team included Lev Tsimring, associate director of the BioCircuits Institute, and bioengineering graduate students Octavio Mondragon, Tal Danino and Jangir Selimkhanov. Their research was supported by grants from the National Institutes of Health and General Medicine and the San Diego Center for Systems Biology.

Для печати
Pharmacy CanadianPharmacyOnlineToUSA.com


Menu
Growing Meat in the Lab: Scientists Initiate Action Plan to Advance Cultured Meat

Recycling Fat Might Help Worms Live Longer

In More Socially Engaging Environment, White Fat Turns to Brown, Mouse Study Suggests

Clouds Don't Cause Climate Change, Study Shows

Novel Magnetic, Superconducting Material Opens New Possibilities in Electronics

New Material Shows Promise for Trapping Pollutants

Breakthrough Could Double Wireless Capacity With No New Towers

Microbes Generate Electricity While Cleaning Up Nuclear Waste

Milky Way Galaxy Might Hold Thousands of Ticking 'Time Bombs'

Neurosurgeons Use Adult Stem Cells to Grow Neck Vertebrae

Jumping Gene's Preferred Targets May Influence Genome Evolution

Peer Pressure? It's Hardwired Into Our Brains, Study Finds

Scientists Create Mammalian Cells With Single Chromosome Set

Evidence for a Persistently Iron-Rich Ocean Changes Views On Earth's Early History

Nanosensors Made from DNA May Light Path to New Cancer Tests and Drugs

Endangered Horse Has Ancient Origins and High Genetic Diversity, New Study Finds

Australopithecus Sediba Paved the Way for Homo Species, New Studies Suggest

Babies Distinguish Pain from Touch at 35-37 Weeks, Research Finds

Mantis Shrimp: Ocean Floor Critters Communicate in Synchronized Rumbles

Powered by Seaweed: Polymer from Algae May Improve Battery Performance

Captivated by Critters: Humans Are Wired to Respond to Animals

Birth Control Pills Affect Memory, Researchers Find

NASA Launches Mission to Study Moon From Crust to Core

Sea Levels Much Less Stable Than Earlier Believed, New Coral Dating Method Suggests

Ferroelectrics Could Pave Way for Ultra-Low Power Computing