Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

The ABC of a stress response

22.03.2010
The identification of a gene involved in the response of plants to water stress should help breed better crop varieties

When plants become desiccated, tiny leaf pores collectively called stomata close to conserve water. Each stoma is flanked by a pair of ‘guard cells’, which change shape to open or close the central pore.

This stress response involves the plant hormone abscisic acid (ABA). When produced in vascular tissues, ABA can act locally within cells via several known ABA receptors. However, to act on distant targets such as guard cells, this hormone must first be released from ABA-producing cells, raising the question of how it crosses the outer cell membrane.

To address this, Takashi Kuromori and colleagues of RIKEN Plant Science Center, Yokohama, screened over 12,000 lines of Arabidopsis—a commonly used plant model—for ABA-related mutants. Their identification of a mutant hypersensitive to ABA at the germination and seedling stages has led to the isolation of a gene encoding a type of ‘ATP-binding cassette (ABC) transporter’.

ABC transporters use chemical energy stored in the biological molecule ATP to transport molecules across cell membranes and are present in organisms from bacteria to animals, including humans, but are especially prevalent in plants.

“Arabidopsis has 130 ABC transporter genes, while rice and beans each have more than 100, which means plants have 2–3 times more than other species,” says Kuromori.“We believe that some kinds of ABC transporters evolved to have important plant-specific functions in plant development and physiological regulation.”

The newly identified transporter, AtABCG25, is expressed mainly in vascular tissues, such as roots and leaf veins. Importantly, this transporter localizes to the outer cell membrane. Some types of ABC transporter localize to membranes surrounding structures within cells which means that they could not transport ABA out of ABA-producing cells to be released into the spaces between cells.

Plants genetically engineered to over express AtABCG25 had higher leaf temperature compared to normal plants and decreased water loss from isolated leaves. The researchers believe that ABA built up in the guard cells of the engineered plants, causing enhanced stomatal closure.

Although it remains unclear how ABA reached the guard cells from vascular tissues, they hope that their findings will lead to the breeding of stress-tolerant crops.

“To date, research on plant stress tolerance has focused on ABA synthesis and/or the expression of ABA target genes,” says Kuromori. “However, our results suggest the possibility of establishing methods to control ABA transport and migration, which could lead to new techniques for breeding stress-tolerant plants.”

The corresponding author for this highlight is based at the Gene Discovery Research Group, RIKEN Plant Science Center.

Journal information

1. Kuromori, T., Miyaji, T., Yabuuchi, H., Shimizu, H., Sugimoto, E., Kamiya, A., Moriyama, Y. & Shinozaki, K. ABC transporter AtABCG25 is involved in abscisic acid transport and responses. Proceedings of the National Academy of Sciences USA 107, 2361–2366 (2010)

Saeko Okada | Research asia research news
Further information:
http://www.rikenresearch.riken.jp/eng/research/6216
http://www.researchsea.com

Further reports about: ABA AtABCG25 Kuromori RIKEN Science TV abscisic acid cell membrane

More articles from Life Sciences:

nachricht How cheetahs stay fit and healthy
24.03.2017 | Forschungsverbund Berlin e.V.

nachricht When Air is in Short Supply - Shedding light on plant stress reactions when oxygen runs short
23.03.2017 | Institut für Pflanzenbiochemie

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Giant Magnetic Fields in the Universe

Astronomers from Bonn and Tautenburg in Thuringia (Germany) used the 100-m radio telescope at Effelsberg to observe several galaxy clusters. At the edges of these large accumulations of dark matter, stellar systems (galaxies), hot gas, and charged particles, they found magnetic fields that are exceptionally ordered over distances of many million light years. This makes them the most extended magnetic fields in the universe known so far.

The results will be published on March 22 in the journal „Astronomy & Astrophysics“.

Galaxy clusters are the largest gravitationally bound structures in the universe. With a typical extent of about 10 million light years, i.e. 100 times the...

Im Focus: Tracing down linear ubiquitination

Researchers at the Goethe University Frankfurt, together with partners from the University of Tübingen in Germany and Queen Mary University as well as Francis Crick Institute from London (UK) have developed a novel technology to decipher the secret ubiquitin code.

Ubiquitin is a small protein that can be linked to other cellular proteins, thereby controlling and modulating their functions. The attachment occurs in many...

Im Focus: Perovskite edges can be tuned for optoelectronic performance

Layered 2D material improves efficiency for solar cells and LEDs

In the eternal search for next generation high-efficiency solar cells and LEDs, scientists at Los Alamos National Laboratory and their partners are creating...

Im Focus: Polymer-coated silicon nanosheets as alternative to graphene: A perfect team for nanoelectronics

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are less stable. Now researchers at the Technical University of Munich (TUM) have, for the first time ever, produced a composite material combining silicon nanosheets and a polymer that is both UV-resistant and easy to process. This brings the scientists a significant step closer to industrial applications like flexible displays and photosensors.

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are...

Im Focus: Researchers Imitate Molecular Crowding in Cells

Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to simulate these confined natural conditions in artificial vesicles for the first time. As reported in the academic journal Small, the results are offering better insight into the development of nanoreactors and artificial organelles.

Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

International Land Use Symposium ILUS 2017: Call for Abstracts and Registration open

20.03.2017 | Event News

CONNECT 2017: International congress on connective tissue

14.03.2017 | Event News

ICTM Conference: Turbine Construction between Big Data and Additive Manufacturing

07.03.2017 | Event News

 
Latest News

When Air is in Short Supply - Shedding light on plant stress reactions when oxygen runs short

23.03.2017 | Life Sciences

Researchers use light to remotely control curvature of plastics

23.03.2017 | Power and Electrical Engineering

Sea ice extent sinks to record lows at both poles

23.03.2017 | Earth Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>