Navigation Links
Unearthing key function of plant hormone

This news release is available in German.

Plants, like animals, employ hormones as messengers, which coordinate growth and regulate how they react to the environment. One of these plant hormones, auxin, regulates nearly all aspects of plant behavior and development, for example phototropism, root growth and fruit growth. Depending on the context, auxin elicits a range of responses such as cell polarization or division. In this week's edition of Science (DOI:10.1126/science.1245125), a team of researchers including Jiri Friml from IST Austria and led by Zhenbiao Yang of the University of California, Riverside, report finding the molecular mechanism by which the plant hormone auxin affects the organization of the cell's inner skeletons.

Auxin is a remarkable molecule, impinging on a variety of plant responses in growth and development. How auxin can play such a range of roles is as yet unexplained, though auxin may activate distinct signaling systems in different contexts and so convey different signals for different responses. For example, a nuclear receptor pathway modulates gene transcription in response to auxin. Auxin binding protein 1 (ABP1) has been proposed to act independently of this nuclear pathway, regulating responses at the plasma membrane and in the cytoplasm. ABP1 was discovered nearly 40 years ago, but how it transmits the auxin signal and regulates responses remained unclear to date. In their Science publication, the researchers show that at the cell surface ABP1 interacts with transmembrane kinases (TMKs). In genetic variants of Arabidopsis in which TMKs are mutated, pathways regulated by ABP1 are impaired such as the characteristic arrangement of pavement cells.

TMKs and ABP1 are also both required for the activation of ROP GTPases, which regulate the organization of the cell's inner skeleton. This cytoskeleton is disrupted when TMKs are mutated, as filamentous actin does not localize correctly and cortical microtubules are disorganized. The researchers show that all of TMK1 as well as around a quarter of ABP1 can be found at the plasma membrane. In the presence of auxin, TMK1 and ABP1 bind to each other. The researchers propose that secreted ABP1 binds to TMK1 at the plasma membrane in response to extracellular auxin, and signal to ROP GTPases which affect the cytoskeleton.

TMK1 is at least one of the long-sought docking proteins of ABP1, which couple extracellular auxin and its perception by ABP1 to downstream cytoplasmic events. Solving the mystery of cell surface-cytoplasmic auxin perception, this research opens up a new horizon in auxin biology.


Contact: Oliver Lehmann
Institute of Science and Technology Austria

Related biology news :

1. Getting to the root -- unearthing the plant-microbe quid pro quo
2. Scientists transform skin cells into functioning liver cells
3. Compound improves cardiac function in mice with genetic heart defect, MU study finds
4. A*STAR scientists discover proteins role in human memory and learning functions
5. Exercise targets cellular powerhouses to improve heart function
6. Paper offers insights into network that plays crucial role in cell function and disease
7. Genetic function discovered that could offer new avenue to cancer therapies
8. People who enjoy life maintain better physical function as they age
9. Diffusion tensor MRI-based tractography in evaluation of nerve root function
10. Cardiac MRI reveals energy drinks alter heart function
11. Human stem cells converted to functional lung cells
Post Your Comments:
Related Image:
Unearthing key function of plant hormone
(Date:11/17/2015)... SOUTH EASTON, Mass. , Nov. 17, 2015 /PRNewswire/ ... "Company"), a leader in the development and sale of ... to the worldwide life sciences industry, today announced it ... closing of its $5 million Private Placement (the "Offering"), ... Offering to $4,025,000.  One or more additional closings are ...
(Date:11/12/2015)... , Nov. 12, 2015  Arxspan has ... of MIT and Harvard for use of its ... information management tools. The partnership will support the ... biological and chemical research information internally and with ... be used for managing the Institute,s electronic laboratory ...
(Date:11/10/2015)...  In this report, the biomarkers market ... type, application, disease indication, and geography. The ... consumables, services, software. The type segments included ... biomarkers, and validation biomarkers. The applications segments ... drug discovery and development, personalized medicine, disease ...
Breaking Biology News(10 mins):
(Date:11/25/2015)... ... November 25, 2015 , ... Jessica ... on AngelList early in their initial angel funding process. Now, they are paying ... looking to make early stage investments in the microbiome space. In this, ...
(Date:11/24/2015)... , Nov. 24, 2015 /CNW/ - iCo Therapeutics ("iCo" ... reported financial results for the quarter ended September ... in Canadian dollars and presented under International Financial ... States ," said Andrew Rae , ... regarding iCo-008 are not only value enriching for ...
(Date:11/24/2015)... 24, 2015 --> ... report "Oligonucleotide Synthesis Market by Product & Services (Primer, ... Diagnostic, DNA, RNAi), End-User (Research, Pharmaceutical & Biotech, Diagnostic ... the market is expected to reach USD 1,918.6 Million ... a CAGR of 10.1% during the forecast period. ...
(Date:11/24/2015)... Ltd. (OTCQB: TIKRF) today announced that its Annual General Meeting of Shareholders ... Israel time, at the law offices of Goldfarb Seligman ... Floor, Tel Aviv, Israel . ... to the Board of Directors; , election of Liat ... an amendment to certain terms of options granted to our Chief Executive ...
Breaking Biology Technology: