A recent Van Andel Research Institute (VARI) study published in the journal Science investigating the molecular structure and function of an essential plant hormone could profoundly change our understanding of a key cell process, and might ultimately lead to the development of new drugs for a variety of diseases.
The study builds on earlier work by the same team of investigators at VARI that was published in the journal Nature in 2009. That study shed light on how plants respond when they are under stress from extreme temperatures, drought and other harsh environmental conditions and was later named by Science as one of the top scientific breakthroughs of 2009.
Understanding how cells talk
In signal transduction – the basic process of intercellular and intracellular communication – enzymes known as kinases and phosphatases serve as the opposing partners and key regulators of this process.
VARI scientists mapping the structure of the receptor for Abscisic acid (ABA), a plant hormone that controls growth, development and responses to environmental stress, discovered that ABA regulates the stress-response pathway by affecting an enzyme belonging to the phosphatase family - which in turn binds to a kinase.
“This process has been little understood,” said Karsten Melcher, Ph.D., Head of the VARI Laboratory of Structural Biology and Biochemistry and co-author of the study. "We believe that the activation mechanism may in many cases also be structural. Phosphatases inactivate the active site like a plug – changing the shape of the kinase.”
"The textbook assumption has been that enzymatic phosphatases inhibit kinases only by taking away phosphates from the kinases. There have been few recorded examples of non-enzymatic phosphatases inhibiting kinases."
Knowing that these enzymes mimic the structure of the opposing enzyme enables scientists to more accurately develop mechanisms to activate or inhibit intercellular and intracellular communication. Inhibiting or activating this process in plant cells could lead to plants that more readily survive drought or other conditions of stress.
Possible impact on the treatment of diseases
In mammalian cells the ability to impact communication has numerous and far-reaching implications. For example, applications that inhibit or activate cell communication in out-of-control metastasizing cancer cells have enormous potential to affect tumor growth.
Writing in the journal Science, where the study was published on January 6, Jeffrey Leung notes that “molecular mimicry might be a common mechanism in many biological processes involving kinase-phosphatase complexes…The structural studies on the core ABA signaling proteins establish a new paradigm for kinase-phosphatase co-regulation and coevolution.”
The possibility of broader scientific implications is also noted by Melcher.
“The current studies take a step back from application and focus back on fundamental cellular mechanisms with a broad implication beyond ABA signaling,” said Melcher.
In their 2009 study in Nature, Melcher and H. Eric Xu, Ph.D., used X-ray crystallography to detail precisely how ABA works at the molecular level. One of ABA’s effects is to cause plant pores to close when plants are stressed so that they can retain as much water as possible.In a follow-up 2010 study published in Nature Structural & Molecular Biology, the VARI team identified several synthetic compounds that fit well with ABA’s many receptors to have the same effect. By finding compounds that can close these pores, researchers’ findings could lead to sprays that use a plant’s natural defenses to help it survive harsh environmental conditions.
The lead authors of the current Science study are Fen-Fen Soon, Ley-Moy Ng, and Edward Zhou. The project was carried out in conjunction and collaboration with scientists from the National University of Singapore, Purdue University, The Scripps Research Institute, Scripps Florida, Shanghai Institute of Materia Medica of the Chinese Academy of Sciences, the Synchrotron Research Center of Northwestern University, and University of California at Riverside.
Links to the study and to the Science editorial cited above can be found here:
http://www.sciencemag.org/content/335/6064/46.fullAbout Van Andel Institute
Joe Gavan | EurekAlert!
Further reports about: > Cellular > Nature Immunology > Structural Biology Laboratory > VAI > VARI > biological process > cellular communication > cellular mechanism > environmental conditions > mental conditions > molecular process > plant cell > plant hormone > signaling protein > synthetic biology > treatment of disease
Mass spectrometry sheds new light on thallium poisoning cold case
14.12.2018 | University of Maryland
Protein involved in nematode stress response identified
14.12.2018 | University of Illinois College of Agricultural, Consumer and Environmental Sciences
The more objects we make "smart," from watches to entire buildings, the greater the need for these devices to store and retrieve massive amounts of data quickly without consuming too much power.
Millions of new memory cells could be part of a computer chip and provide that speed and energy savings, thanks to the discovery of a previously unobserved...
What if, instead of turning up the thermostat, you could warm up with high-tech, flexible patches sewn into your clothes - while significantly reducing your...
A widely used diabetes medication combined with an antihypertensive drug specifically inhibits tumor growth – this was discovered by researchers from the University of Basel’s Biozentrum two years ago. In a follow-up study, recently published in “Cell Reports”, the scientists report that this drug cocktail induces cancer cell death by switching off their energy supply.
The widely used anti-diabetes drug metformin not only reduces blood sugar but also has an anti-cancer effect. However, the metformin dose commonly used in the...
A research team from the University of Zurich has developed a new drone that can retract its propeller arms in flight and make itself small to fit through narrow gaps and holes. This is particularly useful when searching for victims of natural disasters.
Inspecting a damaged building after an earthquake or during a fire is exactly the kind of job that human rescuers would like drones to do for them. A flying...
Over the last decade, there has been much excitement about the discovery, recognised by the Nobel Prize in Physics only two years ago, that there are two types...
12.12.2018 | Event News
10.12.2018 | Event News
06.12.2018 | Event News
14.12.2018 | Power and Electrical Engineering
14.12.2018 | Physics and Astronomy
14.12.2018 | Physics and Astronomy