Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


New mechanism for nutrient uptake discovered

Biologists at the Carnegie Institution's Department of Plant Biology have discovered a new way that plant cells govern nutrient regulation—neighboring pore-like structures at the cell's surface physically interact to control the uptake of a vital nutrient, nitrogen.

It is the first time scientists have found that the interaction of neighboring molecules is essential to this regulation. Since plants, animals, bacteria, and fungi all share similar genes for this activity, the scientists believe that the same feature could occur across species. The discovery, published in the February 11th on-line edition of Nature, has widespread potential—from understanding human diseases, such as kidney function, to engineering better crops.

"Every cell in every organism has a system for bringing in nutrition and expelling waste," explained lead author Dominique Loqué. "Some are through pore-like protein structures called transporters, which reside at the surface of the cell's outer membrane. Each pore is capable of transporting nutrients individually, so we were really surprised to find that the pores simply can't act without stimulation from their neighbors."

In earlier research the Carnegie scientists, with colleagues, identified the genes responsible for initiating nitrogen uptake in plants. That identification has helped other researchers find the relatives of these genes in a variety of species from bacteria to humans. In this study, the scientists wanted to identify how ammonium transport is regulated.

... more about:
»Ammonium »FOR »discovered »nitrogen »nutrient »uptake

Plants import nitrogen in the form of ammonium from the soil. The researchers found that the end portion, or so-called C-terminus, of the protein Arabidopsis ammonium transporter AtAMT1;1, located at the surface of the cell membrane, acts as a switch.

"The terminus is an arm-like feature that physically grabs a neighboring short-chain molecule, binds with it, and changes the shape of itself and its neighbor thereby activating all the pores in the complex," continued Loqué. "The pores can't function without this physical stimulation."

"The rapid chain-reaction among the different pores allows the system to shut down extremely fast and can even memorize previous exposures," noted co-author Wolf Frommer. "Imagine a large animal marking its territory. A sudden flow of ammonia could be toxic to the plant. If it weren't for a rapid-fire shutdown plants could die. The conservation of this feature in the related transporters in bacteria, fungi, plants, and animals suggests that an ancient organism, which was a precursor to all known organisms on Earth, had developed this feature because there was much more ammonia on the early Earth. The ubiquitous presence of this structure in all of the known ammonium transporters suggests that the regulation is still necessary today for all of these organisms—cyanobacteria in the ocean, fungi that grow on grapes and make our wine, plants that provide our food—and even in our kidneys, which excrete nitrogen. We also suspect other different types of transporters will be discovered to work in this way."

The scientists don't yet know what triggers the rapid shut-off. They think it might be a very common regulatory event called phosphorylation, where a phosphate molecule is introduced to another molecule, changing the latter, and preparing it for a chemical reaction. They have found a site for phosphorylation and are looking at this possibility further.

A leading expert in transporters, Professor Dale Sanders, head of the biology department at the University of York in the U.K. commenting on the work said: "Loqué, Frommer and co-workers have demonstrated very beautifully how plant ammonium transporters are controlled. A switch domain in the protein facilitates rapid and sensitive control of ammonium transport to preclude over-accumulation of an ion that is beneficial at low concentrations, but potentially toxic at high concentrations. This is a major advance in the field of plant mineral nutrition."

Wolf Frommer | EurekAlert!
Further information:

Further reports about: Ammonium FOR discovered nitrogen nutrient uptake

More articles from Life Sciences:

nachricht Novel mechanisms of action discovered for the skin cancer medication Imiquimod
21.10.2016 | Technische Universität München

nachricht Second research flight into zero gravity
21.10.2016 | Universität Zürich

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: New 3-D wiring technique brings scalable quantum computers closer to reality

Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.

"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...

Im Focus: Scientists develop a semiconductor nanocomposite material that moves in response to light

In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.

A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...

Im Focus: Diamonds aren't forever: Sandia, Harvard team create first quantum computer bridge

By forcefully embedding two silicon atoms in a diamond matrix, Sandia researchers have demonstrated for the first time on a single chip all the components needed to create a quantum bridge to link quantum computers together.

"People have already built small quantum computers," says Sandia researcher Ryan Camacho. "Maybe the first useful one won't be a single giant quantum computer...

Im Focus: New Products - Highlights of COMPAMED 2016

COMPAMED has become the leading international marketplace for suppliers of medical manufacturing. The trade fair, which takes place every November and is co-located to MEDICA in Dusseldorf, has been steadily growing over the past years and shows that medical technology remains a rapidly growing market.

In 2016, the joint pavilion by the IVAM Microtechnology Network, the Product Market “High-tech for Medical Devices”, will be located in Hall 8a again and will...

Im Focus: Ultra-thin ferroelectric material for next-generation electronics

'Ferroelectric' materials can switch between different states of electrical polarization in response to an external electric field. This flexibility means they show promise for many applications, for example in electronic devices and computer memory. Current ferroelectric materials are highly valued for their thermal and chemical stability and rapid electro-mechanical responses, but creating a material that is scalable down to the tiny sizes needed for technologies like silicon-based semiconductors (Si-based CMOS) has proven challenging.

Now, Hiroshi Funakubo and co-workers at the Tokyo Institute of Technology, in collaboration with researchers across Japan, have conducted experiments to...

All Focus news of the innovation-report >>>



Event News

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

14.10.2016 | Event News

Agricultural Trade Developments and Potentials in Central Asia and the South Caucasus

14.10.2016 | Event News

World Health Summit – Day Three: A Call to Action

12.10.2016 | Event News

Latest News

Resolving the mystery of preeclampsia

21.10.2016 | Health and Medicine

Stanford researchers create new special-purpose computer that may someday save us billions

21.10.2016 | Information Technology

From ancient fossils to future cars

21.10.2016 | Materials Sciences

More VideoLinks >>>