PRESS-NEWS.org - Press Release Distribution
PRESS RELEASES DISTRIBUTION

Scientists identify genetic mechanism that contributed to Irish Famine

Research by UC Riverside plant pathologists is the first to show that RNA silencing regulates plant defense against the notorious Phytophthora pathogens

Scientists identify genetic mechanism that contributed to Irish Famine
2013-02-07
(Press-News.org) RIVERSIDE, Calif. — When a pathogen attacks a plant, infection usually follows after the plant's immune system is compromised. A team of researchers at the University of California, Riverside focused on Phytophthora, the pathogen that triggered the Irish Famine of the 19th century by infecting potato plants, and deciphered how it succeeded in crippling the plant's immune system.

The genus Phytophthora contains many notorious pathogens of crops. Phytophthora pathogens cause worldwide losses of more than $6 billion each year on potato (Phytophthora infestans) and about $2 billion each year on soybean (Phytophthora sojae).

The researchers, led by Wenbo Ma, an associate professor of plant pathology and microbiology, focused their attention on a class of essential virulence proteins produced by a broad range of pathogens, including Phytophthora, called "effectors." The effectors are delivered to, and function only in, the cells of the host plants the pathogens attack. The researchers found that Phytophthora effectors blocked the RNA silencing pathways in their host plants (such as potato, tomato, and soybean), resulting first in a suppression of host immunity and thereafter in an increase in the plants' susceptibility to disease.

"Phytophthora has evolved a way to break the immunity of its host plants," Ma explained. "Its effectors are the first example of proteins produced by eukaryotic pathogens — nucleated single- or multi-cellular organisms — that promote infection by suppressing the host RNA silencing process. Our work shows that RNA silencing suppression is a common strategy used by a variety of pathogens — viruses, bacteria and Phytophthora — to cause disease, and shows, too, that RNA silencing is an important battleground during infection by pathogens across kingdoms."

Study results appeared online Feb. 3 in Nature Genetics.

What is RNA silencing and what is its significance? RNA is made from DNA. Many RNAs are used to make proteins. However, these RNAs can be regulated by "small RNA" (snippets of RNA) that bind to them. The binding leads to suppression of gene expression. Known as RNA gene silencing, this suppression plays an important role in regulating plant growth and development. When RNA silencing is impaired by effectors, the plant is more susceptible to disease.

Basic RNA silencing processes are conserved in plant and mammalian systems. They serve as a major defense mechanism against viruses in plants and invertebrates. RNA silencing has also been implicated in anti-bacterial plant defense. The discovery by Ma's lab is the first to show that RNA silencing regulates plant defense against eukaryotic pathogens.

"Phytophthora effectors have a motif or signature — a specific protein code — that allows the proteins to be delivered into host cells," Ma said. "A similar motif is found in effectors of animal parasites, such as the malaria pathogen Plasmodium, suggesting an evolutionarily conserved means for delivering effectors that affect host immunity."

Next, her lab will work on extensively screening other pathogens and identifying their effectors' direct targets so that novel control strategies can be developed to manage the diseases the pathogens cause.

Ma was joined in the study by UC Riverside's Yongli Qiao, Lin Liu, Cristina Flores, James Wong, Jinxia Shi, Xianbing Wang, Xigang Liu, Qijun Xiang, Shushu Jiang, Howard S. Judelson and Xuemei Chen; Fuchun Zhang at Xinjiang University, China; and Qin Xiong and Yuanchao Wang at Nanjing Agricultural University, China.

The research was supported by a National Science Foundation grant to Ma and grants from the U.S. Department of Agriculture (USDA) to Judelson and Chen.

In 2011, UCR received a $9 million USDA grant to research late blight, caused by Phytophthora infestans, that mainly attacks potatoes and tomatoes. Last year, UCR released avocado rootstocks that can help control Phytophthora root rot, a disease that has eliminated commercial avocado production in many areas of the world.



INFORMATION:

The University of California, Riverside is a doctoral research university, a living laboratory for groundbreaking exploration of issues critical to Inland Southern California, the state and communities around the world. Reflecting California's diverse culture, UCR's enrollment has exceeded 21,000 students. The campus will open a medical school in 2013 and has reached the heart of the Coachella Valley by way of the UCR Palm Desert Center. The campus has an annual statewide economic impact of more than $1 billion. A broadcast studio with fiber cable to the AT&T Hollywood hub is available for live or taped interviews. UCR also has ISDN for radio interviews. To learn more, call (951) UCR-NEWS.


[Attachments] See images for this press release:
Scientists identify genetic mechanism that contributed to Irish Famine

ELSE PRESS RELEASES FROM THIS DATE:

The deep roots of catastrophe

The deep roots of catastrophe
2013-02-07
SALT LAKE CITY, Feb. 7, 2013 – A University of Utah seismologist analyzed seismic waves that bombarded Earth's core, and believes he got a look at the earliest roots of Earth's most cataclysmic kind of volcanic eruption. But don't worry. He says it won't happen for perhaps 200 million years. "What we may be detecting is the start of one of these large eruptive events that – if it ever happens – could cause very massive destruction on Earth," says seismologist Michael Thorne, the study's principal author and an assistant professor of geology and geophysics at the University ...

2 antibodies are better than 1

2013-02-07
Cancer drugs of the new, molecular generation destroy malignant breast tumors in a targeted manner: They block characteristic molecules on tumor cells - receptors for the hormones estrogen or progesterone, or a co-receptor, called HER2, that binds to many growth factors. But about one in every six breast tumors has none of these receptors. Such cancers, called triple-negative, are particularly aggressive and notoriously difficult to treat. Some of these therapy-resistant cancers have a potential molecular target for cancer drugs, a growth-factor receptor called EGFR, ...

A genetic device performs DNA diagnosis

2013-02-07
Scientists hope that one day in the distant future, miniature, medically-savvy computers will roam our bodies, detecting early-stage diseases and treating them on the spot by releasing a suitable drug, without any outside help. To make this vision a reality, computers must be sufficiently small to fit into body cells. Moreover, they must be able to "talk" to various cellular systems. These challenges can be best addressed by creating computers based on biological molecules such as DNA or proteins. The idea is far from outrageous; after all, biological organisms are capable ...

Going along means getting along -- and that's not always good, Baylor study finds

2013-02-07
Caving in to social pressure — such as saying that you love a movie because friends do — makes for good vibes about being part of a group and can produce more of the same conduct, according to a Baylor University sociological study. The finding has implications for people ranging from philanthropists to gangs, researchers said. "The punch line is very simple: Conformity leads to positive feelings, attachments, solidarity — and these are what motivate people to continue their behavior," said Kyle Irwin, Ph.D., an assistant professor of sociology at Baylor and lead author. ...

Observed: The outburst before the blast

2013-02-07
Before they go all-out supernova, certain large stars undergo a sort of "mini-explosion," throwing a good-sized chunk of their material off into space. Though several models predict this behavior and evidence from supernovae points in this direction, actually observations of such pre-explosion outbursts have been rare. In new research led by Dr. Eran Ofek of the Weizmann Institute, scientists found such an outburst taking place a short time – just one month – before a massive star underwent a supernova explosion. The findings, which recently appeared in Nature, help ...

How to improve communication between parents and children after divorce

2013-02-07
How to improve communication between parents and children after divorce Article provided by Law Office of Rebecca Garren Parker Visit us at http://www.rebeccaparkerlaw.com Most people understand that divorce takes a toll on the finances and emotions of a family. However, some may not realize the burden a divorce can place on communication between family members, including communication between former spouses and between parents and children. By following a few simple tips, everyone can improve communication and help redefine and heal relationships after a divorce. Communication ...

How parenting plans work in California

2013-02-07
How parenting plans work in California Article provided by The Law Offices of Daniel S. Frank Visit us at http://www.danielfrankattorney.com A parenting plan, also called a custody and visitation agreement, is a written agreement that where and with whom the child of divorcing parents will and defines the times the child will spend with the non-custodial parent. The main purpose of creating a parenting plan is to agree on how to share time with the child and how the parents will make important decisions regarding the child's welfare, such as education and health. ...

Credit Can Be Restored After Bankruptcy

2013-02-07
Credit Can Be Restored After Bankruptcy Article provided by Mitchell & Malone Visit us at http://www.mitchellmir.com In a tough economy, Texas families may find themselves with more debt than they can handle. Filing for bankruptcy is a workable solution for many Texans, but along with the relief that comes with managing debt may come worries about the long-term financial effects of bankruptcy. Some of those worries are not well founded. In particular, a bankruptcy filing need not permanently ruin a filer's credit, even though the bankruptcy will remain in a ...

California employers gain more control over workplace injury care

2013-02-07
California employers gain more control over workplace injury care Article provided by Atcheson & Kepler Visit us at http://www.workinjury-sandiego.com Residents of San Diego and other areas in California might be aware that a change in state policy makes a new form of treatment option available to employers in the event of an injury connected to a workers' compensation claim. It may be helpful for employees to be aware of these changes and the implications that they have in terms of medical care provided to injured employees. What is a medical provider network? Several ...

Two California News Anchors Fired, Allege Age Discrimination

2013-02-07
Two California News Anchors Fired, Allege Age Discrimination Article provided by Stratton & Green, ALC Visit us at http://www.sglawcorp.com William Schechner and John Lobertini, popular news reporters for KPIX in San Francisco, California, were laid off after CBS required its affiliates to reduce their budgets by 10 percent. The two reporters allege that although they were experienced and performed their jobs well, they were fired based solely on the fact that they were older than most other reporters. If these allegations are true, KPIX would be in violation ...

LAST 30 PRESS RELEASES:

Thirty-year mystery of dissonance in the “ringing” of black holes explained

Less intensive works best for agricultural soil

Arctic rivers project receives “national champion” designation from frontiers foundation

Computational biology paves the way for new ALS tests

Study offers new hope for babies born with opioid withdrawal syndrome

UT, Volkswagen Group of America celebrate research partnership

New Medicare program could dramatically improve affordability for cancer drugs – if patients enroll

Are ‘zombie’ skin cells harmful or helpful? The answer may be in their shapes

University of Cincinnati Cancer Center presents research at AACR 2025

Head and neck, breast, lung and survivorship studies headline Dana-Farber research at AACR Annual Meeting 2025

AACR: Researchers share promising results from MD Anderson clinical trials

New research explains why our waistlines expand in middle age

Advancements in muon detection: Taishan Antineutrino Observatory's innovative top veto tracker

Chips off the old block

Microvascular decompression combined with nerve combing for atypical trigeminal neuralgia

Cutting the complexity from digital carpentry

Lung immune cell type “quietly” controls inflammation in COVID-19

Fiscal impact of expanded Medicare coverage for GLP-1 receptor agonists to treat obesity

State and sociodemographic trends in US cigarette smoking with future projections

Young adults drive historic decline in smoking

NFCR congratulates Dr. Robert C. Bast, Jr. on receiving the AACR-Daniel D. Von Hoff Award for Outstanding Contributions to Education and Training in Cancer Research

Chimpanzee stem cells offer new insights into early embryonic development

This injected protein-like polymer helps tissues heal after a heart attack

FlexTech inaugural issue launches, pioneering interdisciplinary innovation in flexible technology

In Down syndrome mice, 40Hz light and sound improve cognition, neurogenesis, connectivity

Methyl eugenol: potential to inhibit oxidative stress, address related diseases, and its toxicological effects

A vascularized multilayer chip reveals shear stress-induced angiogenesis in diverse fluid conditions

AI helps unravel a cause of Alzheimer's disease and identify a therapeutic candidate

Coalition of Autism Scientists critiques US Department of Health and Human Services Autism Research Initiative

Structure dictates effectiveness, safety in nanomedicine

[Press-News.org] Scientists identify genetic mechanism that contributed to Irish Famine
Research by UC Riverside plant pathologists is the first to show that RNA silencing regulates plant defense against the notorious Phytophthora pathogens