Navigation Links
Evolutionary arms race between smut fungi and maize plants
Date:12/9/2010

Fungi are a major cause of plant diseases and are responsible for large-scale harvest failure in crops like maize and other cereals all over the world. Together with scientists from the Helmholtz Zentrum in Munich, Regine Kahmann, from the Max Planck Institute for Terrestrial Microbiology in Marburg, and Jan Schirawski, who is now based at the University of Gttingen, analysed the genetic make-up of Sporisorium reilianum, an important maize parasite. Based on a comparison with the genome of a related fungal species, they succeeded in identifying new genes that play an important role in maize infestation. (Science, December 10, 2010)

The smut fungi Ustilago maydis and Sporisorium reilianum are parasites that attack maize plants. Ustilago maydis causes a disease known as boil smut or common smut, which is characterized by large tumour-like structures on the leaves, cobs and male flowers in which the fungus proliferates and produces spores. Sporisorium reilianum also attacks maize plants; however, it infects the entire plant and its symptoms become manifested only in the male and female flowers. For this reason, it is also referred to as maize head smut.

Little has been known up to now as to how these pathogens cause disease. Four years ago, a team of scientists headed by the Marburg group succeeded in decoding the genome sequence of Ustilago maydis. They demonstrated that the genes, for a large number of completely new proteins secreted by the fungus, are arranged in groups on the chromosomes in so-called gene clusters. These proteins control the colonisation of the host plant.

Similar and yet different

The researchers were initially only able to demonstrate the presence of these proteins in Ustilago maydis. "However, we found it hard to imagine that these proteins, which play such a crucial role in maize infestation, should only be present in the genome of a single smut fungus. For this reason, we also sequenced the genome of Sporisorium reilianum," explains Regine Kahmann from the Max Planck Institute in Marburg. Over 90 percent of the proteins secreted by Ustilago maydis also exist in Sporisorium reilianum. However, many of these proteins differ significantly between the two species and are therefore difficult to detect at the gene level. "Surprisingly, however, almost all of the genes of the two organisms are arranged in the same order. As a result, we were able to superimpose the two genomes like blueprints and display the differences in this way," says Kahmann.

The scientists discovered 43 so-called divergence regions, in which the differences in the two sets of genes are particularly significant. These included all of the gene clusters identified four years ago, whose genes play an important role in the infection of the host plant. In addition to this, four out of six randomly selected divergence regions influence the strength of Ustilago maydis infection, and surprisingly, one of these does not contain genes for secreted proteins. "This shows that additional, thus far undiscovered molecules control the relationship between the fungus and the plant," comments Jan Schirawski.

Evolutionary struggle between maize and fungus

Therefore, the genes that differ most strongly between the two fungi are in all likelihood those that play an important role in the infestation of the maize plant. The different life styles of Ustilago maydis and Sporisorium reilianum presumably resulted in the development of species-specific gene variants in these fungi over the course of evolution, e. g. to suppress the plant's immune response. The maize plants, in turn, modified the target molecules of these fungal proteins. Maize plants apparently form at least one protein to counteract each of the proteins released by the fungi. "What we see here are the signs of an ongoing struggle between the defending plant and attacking parasite. The variety of the weapons of attack and defence used is the product of an arms race between the plant and the fungus. Each modification on one side is countered by an adaptation on the other," explains Schirawski. With the help of the molecules they discovered on the basis of the differences between the two fungi, the Marburg-based researchers have the long term hope that it will be possible to develop new strategies for disease control of these and related plant parasites.


'/>"/>

Contact: Regine Kahmann
kahmann@mpi-marburg.mpg.de
49-642-117-8501
Max-Planck-Gesellschaft
Source:Eurekalert  

Related biology news :

1. Powdery mildew at an evolutionary dead end
2. SomaLogic researchers describe revolutionary new approach to protein analysis and application to early diagnosis of lung cancer
3. Study rewrites the evolutionary history of C4 grasses
4. Nightshades mating habits strike uneasy evolutionary balance
5. Plants kick-start evolutionary drama of Earths oxygenation
6. Learning to live on land: How some early plants overcame an evolutionary hurdle
7. Researcher finds revolutionary way to treat eye cancer
8. Genetic structure of first animal to show evolutionary response to climate change determined
9. The evolutionary origins of coral sex
10. In the neck of time: Scientists unravel another key evolutionary trait
11. A revolutionary breakthrough in terahertz remote sensing
Post Your Comments:
*Name:
*Comment:
*Email:
Related Image:
Evolutionary arms race between smut fungi and maize plants
(Date:11/30/2016)... Nov. 30, 2016  higi SH llc (higi) ... initiative targeting national brands, industry thought-leaders and celebrity ... respective audiences for taking steps to live healthier, ... in 2012, higi has built the largest self-screening ... 38 million people who have conducted over 185 ...
(Date:11/29/2016)... 29, 2016 Nearly one billion matches per second ... ... DERMALOG is Germany's ... efficient Identity Management. (PRNewsFoto/DERMALOG Identification Systems) ... DERMALOG is Germany's largest Multi-Biometric supplier: The company's Fingerprint Identification ...
(Date:11/22/2016)... , November 22, 2016 According to the ... IRIS, Palm Print, Face, Vein, Signature, Voice), Multi-Factor), Component (Hardware and Software), ... published by MarketsandMarkets, the market is expected to grow from USD 10.74 ... CAGR of 16.79% between 2016 and 2022. ... ...
Breaking Biology News(10 mins):
(Date:12/2/2016)... Diego, CA (PRWEB) , ... December 01, 2016 , ... ... data from its Phase I/II clinical trials for AC0010 at the World Conference on ... forward to providing an update on the phase I/II clinical trials for AC0010 in ...
(Date:12/2/2016)... ... 01, 2016 , ... The Conference Forum has announced that the 3rd annual ... place on February 1-3, 2017 at the Roosevelt Hotel in New York City. Led ... a unique 360-degree approach, which addresses the most up-to-date information regarding business aspects, clinical ...
(Date:12/2/2016)... ... December 02, 2016 , ... Robots will storm the Prudential ... December 3rd, 2016. The event, which is held on the United Nations International Day ... with Disabilities back into the workplace. Suitable Technologies is partnering with NTI to showcase ...
(Date:11/30/2016)... ... November 30, 2016 , ... BEI Kimco, a brand of ... flexure design that ensures high alignment accuracy by preventing unwanted shaft rotation. The ... where extreme precision is required, such as in medical equipment, laboratory instrumentation, clean ...
Breaking Biology Technology: