Biologists at UC San Diego have succeeded in visualizing the movement within plants of a key hormone responsible for growth and resistance to drought.
The achievement will allow researchers to conduct further studies to determine how the hormone helps plants respond to drought and other environmental stresses driven by the continuing increase in the atmosphere’s carbon dioxide, or CO2, concentration.
A paper describing their achievement appears in the April 15 issue of the scientific journal eLife and is accessible here.
The plant hormone the biologists directly tracked is abscisic acid, or ABA, which plays a major role in activating drought resistance responses of plants and in regulating plant growth under environmental stress conditions. The ABA stress hormone also controls the closing of stomata, the pores within leaves through which plants lose 95 percent of their water while taking in CO2 for growth.
Scientists already know the general role that ABA plays within plants, but by directly visualizing the hormone they can now better understand the complex interactions involving ABA when a plant is subjected to drought or other stress.
“Understanding the dynamic distribution of ABA in plants in response to environmental stimuli is of particular importance in elucidating the action of this important plant hormone,” says Julian Schroeder, a professor of biology at UC San Diego who headed the research effort. “For example, we can now investigate whether an increase in the leaf CO2 concentration that occurs every night due to respiration in leaves affects the ABA concentration in stomatal cells.”
The researchers developed what they call a “genetically-encoded reporter” in order to directly and instantaneously observe the movements of ABA within the mustard plant Arabidopsis. These reporters, called “ABAleons,” contain two differentially colored fluorescent proteins attached to an ABA-binding sensor protein. Once bound to ABA, the ABAleons change their fluorescence emission, which can be analyzed using a microscope. The researchers showed that ABA concentration changes and waves of ABA movement could be monitored in diverse tissues and individual cells over time and in response to stress.
“Using this reporter, we directly observed long distance ABA movements from the stem of a germinating seedling to the leaves and roots of the growing plant and, for the first time, we were able to determine the rate of ABA movement within the growing plant,” says Schroeder.
“Using this tool, we now can detect ABA in live plants and see how it is distributed,” says Rainer Waadt, a postdoctoral associate in Schroeder’s laboratory and the first author of the paper. “We are also able to directly see that environmental stress causes an increase in the ABA concentration in the stomatal guard cells that surround each stomatal pore. In the future, our sensors can be used to study ABA distribution in response to different stresses, including CO2 elevations, and to identify other molecules and proteins that affect the distribution of this hormone. We can also learn how fast plants respond to stresses and which tissues are important for the response.”
The study was supported by grants from the National Science Foundation and, in part, the National Institutes of Health and the U.S Department of Energy’s Division of Chemical Sciences, Geosciences, and Biosciences in the Office of Basic Energy Sciences.
Kim McDonald, 858-534-7572, email@example.com
Kim McDonald | Eurek Alert!
Identifying drug targets for leukaemia
02.05.2016 | The Hong Kong Polytechnic University
A cell senses its own curves: New research from the MBL Whitman Center
29.04.2016 | Marine Biological Laboratory
If a person pushes a broken-down car alone, there is a certain effect. If another person helps, the result is the sum of their efforts. If two micro-particles are pushing another microparticle, however, the resulting effect may not necessarily be the sum their efforts. A recent study published in Nature Communications, measured this odd effect that scientists call “many body.”
In the microscopic world, where the modern miniaturized machines at the new frontiers of technology operate, as long as we are in the presence of two...
Researchers from the Max Planck Institute Stuttgart have developed self-propelled tiny ‘microbots’ that can remove lead or organic pollution from contaminated water.
Working with colleagues in Barcelona and Singapore, Samuel Sánchez’s group used graphene oxide to make their microscale motors, which are able to adsorb lead...
Neutron scattering and computational modeling have revealed unique and unexpected behavior of water molecules under extreme confinement that is unmatched by any known gas, liquid or solid states.
In a paper published in Physical Review Letters, researchers at the Department of Energy's Oak Ridge National Laboratory describe a new tunneling state of...
Honeycomb structures as the basic building block for industrial applications presented using holo pyramid
Researchers of the Alfred Wegener Institute (AWI) will introduce their latest developments in the field of bionic lightweight design at Hannover Messe from 25...
Polymer solar cells can be even cheaper and more reliable thanks to a breakthrough by scientists at Linköping University and the Chinese Academy of Sciences (CAS). This work is about avoiding costly and unstable fullerenes.
Polymer solar cells can be even cheaper and more reliable thanks to a breakthrough by scientists at Linköping University and the Chinese Academy of Sciences...
27.04.2016 | Event News
15.04.2016 | Event News
12.04.2016 | Event News
02.05.2016 | Life Sciences
02.05.2016 | Materials Sciences
02.05.2016 | Physics and Astronomy