Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Discovery focuses on the ‘point’ of plant cell development

16.12.2005


Scientists at the John Innes Centre (JIC), Norwich, UK[1], today report a breakthrough in understanding how plant cells control the direction of their growth. The report, in the international scientific journal Nature[2], describes a gene (called SCN1) which controls the activity of an enzyme that is critical to cell growth. The researchers have found that SCN1 keeps cell growth in check.



“This is an exciting discovery because the direction of cell growth is very important in determining the shape of plant cells and this controls the overall shape and structure of the plant”, says Professor Liam Dolan (project leader at JIC). “We already know about some of the processes involved in cell growth but this is a new insight into how they are localised so that cells can be made to grow in a particular direction”.

The researchers made their discovery from studies on root hair formation on roots of the model plant Thale Cress (Arabidopsis thaliana). Root hairs are important to the plant as they dramatically increase the surface area of the roots, providing a large surface through which water and minerals can be absorbed.


These hair cells are of interest to Dr Dolan’s group because of the way they develop from cells on the surface of the root. Initially a small bulge forms in the surface wall of a root cell and from this bulge a root hair develops. The hairs are long thin cells that grow away from the root surface by cell growth at their tip; the tip of the hair cell ‘pushes’ itself away from the root. To understand how cell growth is restricted to just the tip of the cell the scientists compared several mutant plants where hair development and growth was abnormal. In the plants with abnormal development they discovered that the processes needed for cell growth were not localised, consequently root cells could produce multiple root hairs and the root hairs had several growing tips.

They established that this unusual growth was the result of damage to a specific gene (SCN1). SCN1 produces an enzyme (AtrohGDI1) that inactivates another enzyme (AtrbohC) that promotes cell growth. In the mutants, were no AtrohGDI1 is produced, the cell growth enzyme AtrbohC is hyperactivated, and its activity is dispersed around the cell. Consequently, growth gets out of control resulting in the formation of weird cell shapes[3].

Professor Dolan concludes “experiments on the root hairs of the common weed Arabidopsis may seem bizarre but they are giving us valuable new insights into the sophisticated systems that all multicellular organisms such as plants, animals and fungi use to control their growth. The more we understand of how plants direct their development and eventual size, shape and structure, the greater the opportunities we have to breed plants that have been altered to perform better as crops or ornamentals”.

Notes:

1) The John Innes Centre (JIC), Norwich, UK is an independent, world-leading research centre in plant and microbial sciences. The JIC has over 800 staff and students. JIC carries out high quality fundamental, strategic and applied research to understand how plants and microbes work at the molecular, cellular and genetic levels. The JIC also trains scientists and students, collaborates with many other research laboratories and communicates its science to end-users and the general public. The JIC is grant-aided by the Biotechnology and Biological Sciences Research Council.

2) Nature can be contacted at: Nature London
Katharine Mansell, Tel:+44 (0)20 7843 4658; Fax:+44 (0)20 7843 4951
E-mail: k.mansell@nature.com
Sophie Hebden,
Tel: +44 (0)20 7843 4502; Fax:+44 (0)20 7843 4951
E-mail: s.hebden@nature.com
The paper referred to in this release is “A RhoGDP dissociation inhibitor spatially regulates growth of root hair cells. Rachel Carol et al. 2005 Nature”.

3) Root hair cells develop from epidermal root cells (called trichoblasts). Initially a bulge forms on the surface wall of the trichoblast and from this bulge a root hair develops. Root hair cell growth occurs at the tip; the tip of the hair cell ‘pushes’ itself away from the root as the cell elongates in a zone immediately behind the cell tip.

Plant cell growth requires production of reactive oxygen species (ROS) by RHD2/AtrbohC NADPH oxidase. The tip growth seen in root hair cells is correlated with the activity of RHD2/AtrbohC NADPH oxidase and ROS production, which is restricted to the cell tip.

In mutants where root hair development and growth was abnormal ROS production was not localised and this correlated with trichoblasts producing multiple root hairs and root hairs having several growth axis.

The mutated gene (SCN1 = SUPERCENTIPEDE1) encodes a RhoGTPase GDP dissociation inhibitor. SCN1’s enzyme product (AtrohGDI1) represses (inactivates) the AtrbohC NADPH oxidase that produces ROS critical for cell growth. AtrohGDI1 is a component of the mechanism that focuses/restricts AtrbohC NADPH oxidase activity to the cell tip.

Liam Dolan | alfa
Further information:
http://www.jic.ac.uk

More articles from Life Sciences:

nachricht Scientists uncover the role of a protein in production & survival of myelin-forming cells
19.07.2018 | Advanced Science Research Center, GC/CUNY

nachricht NYSCF researchers develop novel bioengineering technique for personalized bone grafts
18.07.2018 | New York Stem Cell Foundation

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Future electronic components to be printed like newspapers

A new manufacturing technique uses a process similar to newspaper printing to form smoother and more flexible metals for making ultrafast electronic devices.

The low-cost process, developed by Purdue University researchers, combines tools already used in industry for manufacturing metals on a large scale, but uses...

Im Focus: First evidence on the source of extragalactic particles

For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.

To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...

Im Focus: Magnetic vortices: Two independent magnetic skyrmion phases discovered in a single material

For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.

Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...

Im Focus: Breaking the bond: To take part or not?

Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.

A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...

Im Focus: New 2D Spectroscopy Methods

Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.

"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Leading experts in Diabetes, Metabolism and Biomedical Engineering discuss Precision Medicine

13.07.2018 | Event News

Conference on Laser Polishing – LaP: Fine Tuning for Surfaces

12.07.2018 | Event News

11th European Wood-based Panel Symposium 2018: Meeting point for the wood-based materials industry

03.07.2018 | Event News

 
Latest News

A smart safe rechargeable zinc ion battery based on sol-gel transition electrolytes

20.07.2018 | Power and Electrical Engineering

Reversing cause and effect is no trouble for quantum computers

20.07.2018 | Information Technology

Princeton-UPenn research team finds physics treasure hidden in a wallpaper pattern

20.07.2018 | Materials Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>