Antagonistic peptides fine-tunes stomatal patterning

Photo credit: Nature

Figure 2: STOMAGEN overexpression on stomatal development intmm hypocotyl epidermis with combinatorial loss-of-function in ER-family genes.

Competitive binding of antagonistic peptides fine-tunes stomatal patterning

Lee J. S., Hnilova M., Maes M., Lin Y.-C L., Putarjunan A., Han S.-K., Avila J., Torii K.  (2015)

in Nature 522,439–443(25 June 2015)

http://www.nature.com/nature/journal/v522/n7557/full/nature14561.html

DOI: 10.1038/nature14561

Abstract

During development, cells interpret complex and often conflicting signals to make optimal decisions. Plant stomata, the cellular interface between a plant and the atmosphere, develop according to positional cues, which include a family of secreted peptides called epidermal patterning factors (EPFs). How these signalling peptides orchestrate pattern formation at a molecular level remains unclear.

Here we report in Arabidopsis that Stomagen (also called EPF-LIKE9) peptide, which promotes stomatal development, requires ERECTA (ER)-family receptor kinases and interferes with the inhibition of stomatal development by the EPIDERMAL PATTERNING FACTOR 2 (EPF2)–ER module. Both EPF2 and Stomagen directly bind to ER and its co-receptor TOO MANY MOUTHS. Stomagen peptide competitively replaced EPF2 binding to ER. Furthermore, application of EPF2, but not Stomagen, elicited rapid phosphorylation of downstream signalling components in vivo.

Our findings demonstrate how a plant receptor agonist and antagonist define inhibitory and inductive cues to fine-tune tissue patterning on the plant epidermis.

How plants organize cellular structures like stomata on their surface

Photo credit: Google

Plants make big decisions with microscopic cellular competition

by Urton J. (2015)

in UW Today -June 17, 2015

http://www.washington.edu/news/2015/06/17

In the age of tablet computers and smart phones, it’s easy to feel inundated and overloaded by information. But on a cellular level, this bombardment is business as usual, and a team of University of Washington researchers has identified a mechanism that some plant cells use to receive complex and contradictory messages from their neighbors.

As they report in a paper published online June 17 in Nature, the team led by UW biology professor and senior author Keiko Torii made its discovery as they explored how plants organize cellular structures on their surface.

Like other multicellular creatures, plants must coordinate activity among many different types of cells and tissues. Messages, demands, warnings and alerts shuttle among cells near and far. These messages determine what jobs cells take on and how they work together to build and maintain tissues and organs. As plants grow, they also use this information to decide where new structures like leaves or roots should go.

Torii, lead author Jin Suk Lee and their colleagues focused on how plants decide where to place stomata: tiny, two-cell openings on the surface that connect the plant’s interior with the outside world. Critical for water and gas exchange, stomata develop on the plant’s surface based largely on signals they receive from neighboring cells.

“Stomata are so important for plant productivity,” said Torii, who is also an investigator with Howard Hughes Medical Institute and the Gordon and Betty Moore Foundation. “They’re small but have a big impact.”

Plants must grow and distribute their stomata evenly on the surface because too many or too few can disrupt water balance or photosynthesis.

Plants exposed to excess amounts of Stomagen – the pro-stomata signal – develop extra stomata in clusters.Jin Suk Lee, Nature

Lee and Torii studied two signals that plant cells release to control where stomata go. These signals are actually proteins, or small molecules that help cells do work and communicate with one another. One is called Stomagen, which promotes stomata development. The other protein messenger — known by its acronym EPF2 — opposes Stomagen by preventing stomata formation.

Read the full article: UW Today