Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Johns Hopkins researchers detect sweet cacophony while listening to cellular cross-talk

22.10.2008
Johns Hopkins scientists were dubious in the early 1980s when they stumbled on small sugar molecules lurking in the centers of cells; not only were they not supposed to be there, but they certainly weren't supposed to be repeatedly attaching to and detaching from proteins, effectively switching them on and off.

The conventional wisdom was that the job of turning proteins on and off -- and thus determining their actions -- fell to phosphates, in a common and easy-to-detect chemical step in which phosphates fasten to and unfasten from proteins; a process called phosphorylation.

Now, after decades of investigating the "new" sugar-based protein modification they discovered, the Johns Hopkins team admits that they themselves were surprised by their latest results. Published recently in the Proceedings of the National Academy of Sciences, their findings show that the surreptitious sugar switch is likely as influential and ubiquitous as its phosphate counterpart and, indeed, even plays a role in regulating phosphorylation itself.

More to the point, the work has implications for finding new treatments for a number of diseases such as diabetes, neurodegeneration and cancer, because the new switches form yet another potential target for manipulation by drugs.

"Like dark matter in the cosmos, it's hard to find even though it's very abundant," says Gerald Hart, Ph.D., the DeLamar Professor and director of biological chemistry at the Johns Hopkins School of Medicine, referring to the sugar (O-GlcNAc, pronounced oh-GLICK-nac) that carries out GlcNAcylation.

For years, Hart's team thought of GlcNAcylation as phosphorylation's foil; a simple, classic case of either-or. New technologies involving molecular sleuthing with a mass spectrometer allowed them to measure the extent to which the addition of sugar to proteins affects phosphorylation.

Of 428 sites on which phosphate was being added to and taken off of proteins, all responded in some way to increased O-GlcNAc: 280 decreased phosphorylation and 148 increased phosphorylation.

"The influence of sugar is striking," Hart says. "The presence of O-GlcNAc causes the enzymes that add the phosphate to do something different, and this cross-talk itself can modify proteins."

Because both sugar and phosphate modifications are linked to how cells work, they are fundamental to understanding and eventual control of the molecular processes that underlie many diseases.

"With regard to cancer, diabetes and Alzheimer's," says Hart, "most people in the world today have been studying the yang (phosphorylation) but not the yin (GlcNAcylation). There's another whole side that people were unaware of where diabetes diagnostics and cancer therapies could be targeted."

The research was funded by the National Institutes of Health.

Authors on the paper are Zihao Wang, Marjan Gucek and Gerald W. Hart, all of Johns Hopkins.

Maryalice Yakutchik | EurekAlert!
Further information:
http://www.jhmi.edu
http://www.pnas.org/
http://biolchem.bs.jhmi.edu/members/facultydetail.asp?PersonID=679

More articles from Life Sciences:

nachricht Researchers uncover protein-based “cancer signature”
05.12.2016 | Universität Basel

nachricht The Nagoya Protocol Creates Disadvantages for Many Countries when Applied to Microorganisms
05.12.2016 | Leibniz-Institut DSMZ-Deutsche Sammlung von Mikroorganismen und Zellkulturen GmbH

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Shape matters when light meets atom

Mapping the interaction of a single atom with a single photon may inform design of quantum devices

Have you ever wondered how you see the world? Vision is about photons of light, which are packets of energy, interacting with the atoms or molecules in what...

Im Focus: Novel silicon etching technique crafts 3-D gradient refractive index micro-optics

A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.

Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...

Im Focus: Quantum Particles Form Droplets

In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.

“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...

Im Focus: MADMAX: Max Planck Institute for Physics takes up axion research

The Max Planck Institute for Physics (MPP) is opening up a new research field. A workshop from November 21 - 22, 2016 will mark the start of activities for an innovative axion experiment. Axions are still only purely hypothetical particles. Their detection could solve two fundamental problems in particle physics: What dark matter consists of and why it has not yet been possible to directly observe a CP violation for the strong interaction.

The “MADMAX” project is the MPP’s commitment to axion research. Axions are so far only a theoretical prediction and are difficult to detect: on the one hand,...

Im Focus: Molecules change shape when wet

Broadband rotational spectroscopy unravels structural reshaping of isolated molecules in the gas phase to accommodate water

In two recent publications in the Journal of Chemical Physics and in the Journal of Physical Chemistry Letters, researchers around Melanie Schnell from the Max...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ICTM Conference 2017: Production technology for turbomachine manufacturing of the future

16.11.2016 | Event News

Innovation Day Laser Technology – Laser Additive Manufacturing

01.11.2016 | Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

 
Latest News

IHP presents the fastest silicon-based transistor in the world

05.12.2016 | Power and Electrical Engineering

InLight study: insights into chemical processes using light

05.12.2016 | Materials Sciences

High-precision magnetic field sensing

05.12.2016 | Power and Electrical Engineering

VideoLinks
B2B-VideoLinks
More VideoLinks >>>