text-only page produced automatically by LIFT Text Transcoder Skip all navigation and go to page contentSkip top navigation and go to directorate navigationSkip top navigation and go to page navigation
National Science Foundation
News
design element
News
News From the Field
For the News Media
Special Reports
Research Overviews
NSF-Wide Investments
Speeches & Lectures
NSF Current Newsletter
Multimedia Gallery
News Archive
News by Research Area
Arctic & Antarctic
Astronomy & Space
Biology
Chemistry & Materials
Computing
Earth & Environment
Education
Engineering
Mathematics
Nanoscience
People & Society
Physics
 

Email this pagePrint this page


Press Release 05-083
Plant Sacrifices Cells to Fight Invaders

Gene ensures programmed cell suicide does not go unchecked

Depiction of virus invading plant cells

Plants create a zone of dead cells around viral infection site.
Credit and Larger Version

May 19, 2005

Researchers recently discovered a gene essential to one of the plant kingdom's key immune responses--programmed cell death (PCD).  Plants use PCD to create a protective zone of dead cells around the infection site to prevent the invading pathogen from spreading.  But how the plants keep from killing themselves after they turn on the cell-suicide process was a mystery.

Now, in the May 20 issue of the journal Cell, Yale University's Savithramma Dinesh-Kumar and his colleagues report finding a gene that normally propagates a "pro-survival" signal in plant tissue.  Without that input, an alternate "pro-death" signal moves out of the infected areas and damages the rest of the plant.

The group studied the plant-pathogen interactions in a type of tobacco easily infected with a virus in the laboratory. The model system allowed the researchers to inactivate, or silence, a gene important to the plant's PCD response.  In particular, when the gene was inactivated, the plant was unable to regulate the extent of PCD, leading to excessive cell death throughout the plant.

When a plant pathogen makes contact with its intended target, the plant cells immediately launch a set of sophisticated molecular responses.  Such defense mechanisms, including PCD, are similar to immune responses exhibited by animal cells when they are fighting a disease-causing agent. 

In fact, PCD is a well-researched, yet still puzzling phenomenon that has been described in virtually all cell types, both plant and animal.  PCD plays a critical role in many biological processes including immune system function, embryonic development and elimination of defective cells.  When PCD malfunctions, or is undermined by pathogens, the effects can be devastating, resulting in diseases such as cancer, Alzheimer's and AIDS.

Dinesh-Kumar, whose work is supported by the National Science Foundation's (NSF) Plant Genome Research program, had to first develop the gene-silencing technique to adequately inactivate the plant genes.  The new technique was a success for the field of plant research and is currently being used by several research groups.  NSF's Jane Silverthorne said, "This is a great example of how NSF-supported tools are enabling important basic research in plants with a broader relevance to other organisms."

-NSF-

Media Contacts
Richard (Randy) Vines, NSF, (703) 292-7963, rvines@nsf.gov

Program Contacts
Jane Silverthorne, NSF, (703) 292-8470, jsilvert@nsf.gov

Principal Investigators
Savithramma Dinesh-Kumar, Yale University, (203) 432-9965, savithramma.dinesh-kumar@yale.edu

The National Science Foundation (NSF) is an independent federal agency that supports fundamental research and education across all fields of science and engineering. In fiscal year (FY) 2014, its budget is $7.2 billion. NSF funds reach all 50 states through grants to nearly 2,000 colleges, universities and other institutions. Each year, NSF receives about 50,000 competitive requests for funding, and makes about 11,500 new funding awards. NSF also awards about $593 million in professional and service contracts yearly.

 Get News Updates by Email 

Useful NSF Web Sites:
NSF Home Page: http://www.nsf.gov
NSF News: http://www.nsf.gov/news/
For the News Media: http://www.nsf.gov/news/newsroom.jsp
Science and Engineering Statistics: http://www.nsf.gov/statistics/
Awards Searches: http://www.nsf.gov/awardsearch/

 

Leaf damage from uncontrolled PCD
Programmed cell death (PCD) is normally restricted to infection sites.
Credit and Larger Version



Email this pagePrint this page
Back to Top of page