Navigation Links
Plant growth hormones: Antagonists cooperate
Date:6/24/2010

This release is available in German.

The two most important growth hormones of plants, so far considered antagonists, also work synergistically. The activities of auxin and cytokinin, key molecules for plant growth and the formation of organs, such as leaves and buds, are in fact more closely interwoven than previously assumed. Scientists from Heidelberg, Tbingen (Germany) and Umea (Sweden) made this surprising discovery in a series of complex experiments using thale cress (Arabidopsis thaliana), a biological reference organism. The international team of researchers, led by Jan Lohmann, stem cell biologist at Heidelberg University, have now published their results in the scientific journal "Nature". (Nature, 24. Juni 2010)

All the above-ground parts of a plant leaves, buds, stems and seeds ultimately arise from a small tissue at the shoot tip, which contains totipotent stem cells. Since plant stem cells remain active over the entire life of the organism, plants, unlike animals, are able to grow and develop new organs over many decades. On the periphery of the tip, auxin triggers cells to leave the pool of stem cells, differentiate and form organs like leaves and buds. Cytokinin stimulates stem cells to divide and proliferate; it maintains the number of cells and thus the plant's growth potential.

Some of the genetic factors involved in cytokinin's effect on plant growth were already known. In the thale cress experiments, which concentrated on the growth zone at the tip of the shoot, Lohmann and his team now studied the role of auxin in the interplay of the two hormones. It turns out that auxin directly interferes with a feedback loop involving two genes activated by cytokinin ARR7 and ARR15 which limit the effect of cytokinin. Auxin suppresses these two genes, thereby boosting the effect of cytokinin.

"Auxin acts to support the pool of stem cells", explains Jan Lohmann. "When it triggers cells at the periphery of the growth zone to form organs, it still needs to ensure that enough stem cells are supplied." This keeps the number of stem cells from falling below a critical minimum, which is key for plant growth and survival. "We're gradually beginning to understand how hormonal and genetic factors are interwoven to maintain the activity of the growth zone. We now know that hormones and genes interact in multiple ways, each one affecting the other. There are no solitary factors."


'/>"/>

Contact: Jan Lohmann
jlohmann@meristemania.org
49-622-154-6269
Max-Planck-Gesellschaft
Source:Eurekalert  

Related biology news :

1. Gender-bending fish problem in Colorado creek mitigated by treatment plant upgrade
2. Citizen science: Birders contribute valuable data on invasive plant species
3. Mass. General researchers develop functional, transplantable rat liver grafts
4. Cycad plant depends on insect for multiple services
5. Plant disease -- more than a crop killer
6. Coral transplantation the simple and cheap solution to reef restoration
7. Cell Transplantation reports consistent and successful islet isolations offer diabetes hope
8. Plants spice up their sex life with defensins
9. Rare carnivorous plant on top 10 list of newly discovered species
10. Grinding mouth, wrinkle eye: Penn graduate student describes new species of plant-eating dinosaur
11. Discovery: Yeast make plant hormone that speeds infection
Post Your Comments:
*Name:
*Comment:
*Email:
Related Image:
Plant growth hormones: Antagonists cooperate
(Date:8/23/2017)... public,s help is being enlisted in what,s thought to be the biggest ... human body –and are believed to affect health.  ... The Microbiome Immunity Project is the largest study to date ... project's goal is to help advance scientific knowledge of the role of ... The ...
(Date:6/30/2017)... Today, American Trucking Associations announced Seeing ... and eye tracking software, became the newest member ... "Artificial intelligence and advanced sensing algorithms ... driver,s attentiveness levels while on the road.  Drivers ... fatigue and prevent potential accidents, which could lead ...
(Date:5/23/2017)... 23, 2017  Hunova, the first robotic gym for the rehabilitation and ... launched in Genoa, Italy . The first 30 robots ... the USA . The technology was developed and patented ... the IIT spin-off Movendo Technology thanks to a 10 million euro investment ... please click: ...
Breaking Biology News(10 mins):
(Date:10/12/2017)... , ... October 12, 2017 , ... ... Vilnius, Lithuania, announced today that they have entered into a multiyear collaboration to ... provide CRISPR researchers with additional tools for gene editing across all applications. , ...
(Date:10/12/2017)... ... October 12, 2017 , ... BioMedGPS announces expanded ... of its newest module, US Hemostats & Sealants. , SmartTRAK’s US Market for ... fibrin sealants, synthetic sealants and biologic sealants used in surgical applications. BioMedGPS estimates ...
(Date:10/12/2017)... ... October 12, 2017 , ... ... genomics analysis platform specifically designed for life science researchers to analyze and ... researcher Rosalind Franklin, who made a major contribution to the discovery of ...
(Date:10/11/2017)... ... October 11, 2017 , ... The ... endogenous context, enabling overexpression experiments and avoiding the use of exogenous expression plasmids. ... is transformative for performing systematic gain-of-function studies. , This complement to loss-of-function ...
Breaking Biology Technology: