Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

In pursuit of flat growth in leaves

05.10.2016

How does a set of plant cells grow from a bump into a flat leaf that can efficiently capture sunlight? In a paper published this week in PNAS, EMBL scientists show how different types of molecules on the top and bottom of a leaf keep each other in check, ensuring the leaf grows flat.

As a leaf develops, its cells create two different tissues, one on each side of the leaf. Scientists knew that only cells in the top side produce proteins called Class III HD-ZIPs. In the bottom layer, these Class IIIs are suppressed by another set of molecules called microRNA165/166. But how are those microRNAs confined to the bottom side?


If the molecular balance is disturbed, leaves grow stem-like (right), instead of flattening out. PHOTO: Paz Merelo/EMBL


Normally (left), the microRNAs (green) are only found in the cells that will form the bottom side of the leaf. But in the absence of Class IIs (right) they were present throughout the young leaves. IMAGE: Paz Merelo/EMBL

Marcus Heisler’s labs at EMBL and at the University of Sydney found that the Class IIIs in the top tissues of the leaf act together with some closely related proteins, the Class IIs, to suppress the microRNAs.

When Paz Merelo, a postdoc in Heisler’s lab at EMBL, examined Arabidopsis plants in which these Class IIs were not functioning, the microRNAs were no longer inhibited in the top side of the growing leaves. 

So in the absence of Class IIs, the Class IIIs alone aren’t able to counter the microRNAs. The microRNAs can then switch off the Class IIIs on both the bottom and the top of the leaves, and consequently the leaves don’t flatten out, but grow stem-like.

“The activities of the Class III HD-ZIPs and microRNAs somehow have to be perfectly balanced, right from the beginning, to get a nice leaf,” says Heisler.  “And that seems unlikely to happen on its own: so what’s maintaining this balance?”

Heisler and colleagues are following up on the work, looking into how the balance between ‘top’ and ‘bottom’ factors is maintained, honing in on exactly how Class IIIs and Class IIs work together, and investigating other molecules that are restricted to only one side of a growing leaf.

The study was a collaboration with Stephan Wenkel’s lab at the University of Copenhagen.

  • Full bibliographic informationMerelo et al. Regulation of MIR165/166 by Class II and Class III homeodomain leucine zipper proteins establishes leaf polarity. PNAS Early Edition, to be published the week of 3 October 2016. DOI: 10.1073/pnas.1516110113

http://s.embl.org/pr031016

For further information, please contact:

Sonia Furtado

+ 49 6221 387 8263

sonia.furtado@embl.de

Sonia Furtado | AlphaGalileo

More articles from Life Sciences:

nachricht Multifunctional bacterial microswimmer able to deliver cargo and destroy itself
26.04.2018 | Max-Planck-Institut für Intelligente Systeme

nachricht ADP-ribosylation on the right track
26.04.2018 | Max-Planck-Institut für Biologie des Alterns

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Why we need erasable MRI scans

New technology could allow an MRI contrast agent to 'blink off,' helping doctors diagnose disease

Magnetic resonance imaging, or MRI, is a widely used medical tool for taking pictures of the insides of our body. One way to make MRI scans easier to read is...

Im Focus: BAM@Hannover Messe: innovative 3D printing method for space flight

At the Hannover Messe 2018, the Bundesanstalt für Materialforschung und-prüfung (BAM) will show how, in the future, astronauts could produce their own tools or spare parts in zero gravity using 3D printing. This will reduce, weight and transport costs for space missions. Visitors can experience the innovative additive manufacturing process live at the fair.

Powder-based additive manufacturing in zero gravity is the name of the project in which a component is produced by applying metallic powder layers and then...

Im Focus: Molecules Brilliantly Illuminated

Physicists at the Laboratory for Attosecond Physics, which is jointly run by Ludwig-Maximilians-Universität and the Max Planck Institute of Quantum Optics, have developed a high-power laser system that generates ultrashort pulses of light covering a large share of the mid-infrared spectrum. The researchers envisage a wide range of applications for the technology – in the early diagnosis of cancer, for instance.

Molecules are the building blocks of life. Like all other organisms, we are made of them. They control our biorhythm, and they can also reflect our state of...

Im Focus: Spider silk key to new bone-fixing composite

University of Connecticut researchers have created a biodegradable composite made of silk fibers that can be used to repair broken load-bearing bones without the complications sometimes presented by other materials.

Repairing major load-bearing bones such as those in the leg can be a long and uncomfortable process.

Im Focus: Writing and deleting magnets with lasers

Study published in the journal ACS Applied Materials & Interfaces is the outcome of an international effort that included teams from Dresden and Berlin in Germany, and the US.

Scientists at the Helmholtz-Zentrum Dresden-Rossendorf (HZDR) together with colleagues from the Helmholtz-Zentrum Berlin (HZB) and the University of Virginia...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Invitation to the upcoming "Current Topics in Bioinformatics: Big Data in Genomics and Medicine"

13.04.2018 | Event News

Unique scope of UV LED technologies and applications presented in Berlin: ICULTA-2018

12.04.2018 | Event News

IWOLIA: A conference bringing together German Industrie 4.0 and French Industrie du Futur

09.04.2018 | Event News

 
Latest News

European particle-accelerator community publishes the first industry compendium

26.04.2018 | Physics and Astronomy

Multifunctional bacterial microswimmer able to deliver cargo and destroy itself

26.04.2018 | Life Sciences

Why we need erasable MRI scans

26.04.2018 | Medical Engineering

VideoLinks
Science & Research
Overview of more VideoLinks >>>