Brightsurf Science News and Current Science News Events

 
Email a Friend Send to a friend
Printer Friendly Print Pathogen virulence proteins suppress plant immunity

Pathogen virulence proteins suppress plant immunity

April 22, 2008

Blacksburg, Va. - Researchers from the Virginia Bioinformatics Institute (VBI) at Virginia Tech and their colleagues have identified a key function of a large family of virulence proteins that play an important role in the production of infectious disease by the plant pathogen Phytophthora sojae.

VBI Professor Brett Tyler and members of his research group, along with researchers from Virginia Tech's Department of Plant Pathology, Physiology and Weed Science, Nanjing Agricultural University in China, and Wageningen University in The Netherlands, examined the function of the virulence (or effector) protein Avr1b in P. sojae and discovered that Avr1b is capable of suppressing an important process in plant immunity called programmed cell death. Programmed cell death is an in-built suicide mechanism that kills infected plant tissue and fills it with toxins so the pathogen can no longer feed on it. The work appears in the advance online edition of The Plant Cell. (1)




P. sojae is an oomycete plant pathogen that causes severe damage to soybean crops, resulting in $1-2 million in annual losses for commercial farmers in the United States and much more worldwide. By changing key amino acid residues in the effector protein, the researchers were able to attribute the cause of the suppression of programmed cell death to the presence of two conserved sequences (dubbed W and Y motifs) at one particular end of the protein, the C-terminus. These amino acid sequences are also present in many other members of a huge virulence gene superfamily that Tyler's group found recently in oomycete pathogens. (2)

According to VBI Professor Brett Tyler, "Our results suggest that, like many human viruses such as HIV, oomycete plant pathogens disable the immune systems of their victims as part of their infection strategy."
###

The research was supported by funding from the National Research Initiative of the United States Department of Agriculture's Cooperative State Research, Education and Extension Service, the National Science Foundation, the Government of China, and the Netherlands Genomics Initiative.

(1) Daolong D, Kale SD, Wang X, Chen Y, Wang Q, Wang X, Jiang RHY, Arredondo FD, Anderson RG, Thakur PB, McDowell JM, Wang Y, Tyler BM (2008) Conserved C-terminal motifs required for avirulence and suppression of cell death by Phytophthora sojae effector Avr1b. The Plant Cell Published on April 4, 2008; 10.1105/tpc.107.057067.

(2) Jiang R, Tripathy S, Govers F, Tyler BM (2008) RXLR effector reservoir in two Phytophthora species is dominated by a single rapidly evolving superfamily with more than 700 members. Proc. Natl Acad. Sci. USA 105(12): 4874-4879.

Virginia Tech



Related Phytophthora News Articles Phytophthora News and Current Phytophthora Events RSS Phytophthora News and Current Phytophthora Events RSS
Huge virulence gene superfamily responsible for devastating plant diseases
A research team from the Virginia Bioinformatics Institute at Virginia Tech has identified an enormous superfamily of pathogen genes involved in the infection of plants.

Challenges remain in reintroducing American chestnut
Researchers have developed a breed of American chestnut that is resistant to the fungal blight that decimated its population in the early 1900s.

Humans fostering forest-destroying disease
Enjoying your August vacation? Well, (as they say in the summer movies) there's a killer in the woods. Its strike has been consistently quiet, sudden, and deadly.

Californians urged to help reduce spread of Sudden Oak Death
An update on the increased spread of Sudden Oak Death, a plant disease devastating many of California's coastal oak and tanoak trees, and information on what Californians can do to help reduce its spread will be presented during a news conference on plant diseases that are of importance to California's economy and agriculture.

Scientists expand microbe 'gene language'
An international group of scientists has expanded the universal language for the genes of both disease-causing and beneficial microbes and their hosts.

Genome info from 'plant destroyers' could save trees, beans and chocolate
An international team of scientists has published the first two genome sequences from a destructive group of plant pathogens called Phytophthora-a name that literally means "plant destroyer."

Sequences reveal benign origin of deadly plant pathogens
An international team of researchers has published the draft genome sequences of two deadly plant pathogens, Phytophthora ramorum and Phytophthora sojae.

Malaria, potato famine pathogen share surprising trait
Two wildly different pathogens — one that infects vegetables, the other infecting humans—essentially use the same protein code to get their disease-causing proteins into the cells of their respective hosts.

Virginia Bioinformatics Institute launches microbial database
Researchers at the Virginia Bioinformatics Institute at Virginia Tech have launched a publicly-available microbial database to host a range of microbial genome sequences.

New research approach required to combat more aggressive and adaptable Phytophthora
The potato late blight pathogen has become more aggressive since the arrival of a new type of Phytophthora in Europe circa 1976. Moreover, it is able to genetically adapt to new conditions more rapidly. As a consequence, research aimed at solving the problems caused by this disease must be on a larger scale and involve even greater cooperation than was previously the case. This is proven by the thesis with which Wilbert Flier recently obtained his doctorate at Wageningen University. Flier's findings support the initiatives taken by the Wagenningen University and Researchcentre to arrive at a ten-year plan for collaboration with government and industry. This plan aims to design compatible t
More Phytophthora News Articles
Phytophthora Diseases Worldwide
by Donald C. Erwin, Olaf K. Ribeiro


Sprinkler rot of apple and pear (Extension bulletin)
by Gary G Grove


A genetic study of phytophthora infestans using RAPD markers
by Kyle N Landskroener


Jarrah dieback: The dynamics and management of Phytophthora cinnamomi in the jarrah (Eucalyptus marginata) forest of south-western Australia (Research bulletin)
by B. L Shearer


The genus phytophthora diagnoses (or descriptions) and figures from the original papers (Commonwealth Mycological Institute. Miscellaneous publications; no 12)
by Grace Marion Waterhouse


Inbreeding, heterosis, fertility, plasmon differentiation and Phytophthora resistance in Solanum verrucosum Schlechtd.,: And some interspecific crosses in Solanum (Agricultural research reports, 748)
by M. M. F Abdalla


Annotated bibliography of littleleaf and tree decline diseases caused by Phytophthora cinnamomi rands (Technical paper / Department of Forestry)
by Frank H Tainter


Phytophthora and forest management in Australia: Report of a conference held at CSIRO Division of Forest Research, Canberra, 18-20 October 1978


Diseases caused by Phytophthora and Pythium in Sabah, Malaysia (Technical bulletin - Department of Agriculture, Sabah, Malaysia ; no. 3)
by P. S. W Liu


Phytophthora root rot of alfalfa
by Don Allen Roth


© 2008 BrightSurf.com