Nav: Home

Fishing a line coupled with clockwork for daily rhythm

June 06, 2019

Organisms on this planet, including human beings, exhibit a biological rhythm that repeats about every 24 h to adapt to the daily environmental alteration caused by the rotation of the earth. This circadian rhythm is regulated by a set of biomolecules working as a biological clock. In cyanobacteria (or blue-green algae), the circadian rhythm is controlled by the assembly and disassembly of three clock proteins, namely, KaiA, KaiB, and KaiC. KaiC forms a hexameric-ring structure and plays a central role in the clock oscillator, which works by consuming ATP, the energy currency molecule of the cell. However, it remains unknown how the clock proteins work autonomously for generating the circadian oscillation.

The research groups at Graduate School of Pharmaceutical Sciences of Nagoya City University and Exploratory Research Center on Life and Living Systems (ExCELLS) and Institute for Molecular Science (IMS) of National Institutes of Natural Sciences investigated this mechanism by native mass spectrometry and nuclear magnetic resonance spectroscopy. They found that KaiC degrades ATP into ADP within its ring structure, which triggers the leaping out of the tail of KaiC from the ring. KaiA captures the exposed KaiC tail, facilitating ADP release from the ring, thereby setting the clock ahead.

This "fishing a line" mechanism explains the clockwork interplay of the KaiA and KaiC proteins. Elucidating this mechanism will provide deep insights into not only the circadian clock in cyanobacteria but also that in plants, animals, and humans under physiological and pathological conditions, including jet lag and sleep disorders.
-end-


National Institutes of Natural Sciences

Related Circadian Clock Articles:

The discovery of new compounds for acting on the circadian clock
The research team comprised of Designated Associate Professor Tsuyoshi Hirota and Postdoctoral Fellows Simon Miller and Yoshiki Aikawa, of the Nagoya University Institute of Transformative Bio-Molecules, has succeeded in the discovery of novel compounds to lengthen the period of the circadian clock, and has shed light on their mechanisms of action.
Let there be 'circadian' light
Researchers publishing in Current Biology describe the science behind creating lighting to make us all happy and productive indoors.
U of M research discovers link between stress and circadian clock health
New research from the University of Minnesota Medical School found a little stress can make the circadian clock run better and faster.
The role of GABA neurons in the central circadian clock has been discovered
Temporal order of physiology and behavior is regulated by the central circadian clock located in the SCN.
Researchers take aim at circadian clock in deadly brain cancer
Scientists at USC and UC San Diego have discovered a potential novel target for treating glioblastoma, the deadly brain cancer that took the life of Sen.
Circadian clock and fat metabolism linked through newly discovered mechanism
Princeton University researchers found that the enzyme Nocturnin, known for its role in fat metabolism and circadian rhythm, acts on two well-established molecules in metabolism.
Dead zones in circadian clocks
Circadian clocks of organisms respond to light signals during night but do not respond in daytime.
Circadian clock plays unexpected role in neurodegenerative diseases
Northwestern University researchers induced jet lag in a fruit fly model of Huntington disease and found that jet lag protected the flies' neurons.
Researchers locate circadian clock that controls daily rhythms of aggression
Synchronized by light and darkness, the circadian clock exerts control over wake/sleep cycles, body temperature, digestion, hormonal cycles and some behavior patterns.
The rhythm of genes: How the circadian clock regulates 3-D chromatin structure
EPFL biologists and geneticists have uncovered how the circadian clock orchestrates the 24-hour cycle of gene expression by regulating the structure of chromatin, the tightly wound DNA-protein complex of the cell.
More Circadian Clock News and Circadian Clock Current Events

Trending Science News

Current Coronavirus (COVID-19) News

Top Science Podcasts

We have hand picked the top science podcasts of 2020.
Now Playing: TED Radio Hour

Teaching For Better Humans 2.0
More than test scores or good grades–what do kids need for the future? This hour, TED speakers explore how to help children grow into better humans, both during and after this time of crisis. Guests include educators Richard Culatta and Liz Kleinrock, psychologist Thomas Curran, and writer Jacqueline Woodson.
Now Playing: Science for the People

#556 The Power of Friendship
It's 2020 and times are tough. Maybe some of us are learning about social distancing the hard way. Maybe we just are all a little anxious. No matter what, we could probably use a friend. But what is a friend, exactly? And why do we need them so much? This week host Bethany Brookshire speaks with Lydia Denworth, author of the new book "Friendship: The Evolution, Biology, and Extraordinary Power of Life's Fundamental Bond". This episode is hosted by Bethany Brookshire, science writer from Science News.
Now Playing: Radiolab

Space
One of the most consistent questions we get at the show is from parents who want to know which episodes are kid-friendly and which aren't. So today, we're releasing a separate feed, Radiolab for Kids. To kick it off, we're rerunning an all-time favorite episode: Space. In the 60's, space exploration was an American obsession. This hour, we chart the path from romance to increasing cynicism. We begin with Ann Druyan, widow of Carl Sagan, with a story about the Voyager expedition, true love, and a golden record that travels through space. And astrophysicist Neil de Grasse Tyson explains the Coepernican Principle, and just how insignificant we are. Support Radiolab today at Radiolab.org/donate.