Navigation Links
Tiny molecules protect from the dangers of sex
Date:11/14/2010

DURHAM, N.C. Pathogenic fungi have been found to protect themselves against unwanted genetic mutations during sexual reproduction, according to researchers at Duke University Medical Center. A gene-silencing pathway protects the fungal genome from mutations imposed by a partner during mating.

This pathway was discovered in Cryptococcus neoformans, a fungus that commonly infects humans, causing over one million cases of lung and brain infection each year, and more than 600,000 deaths. A related species, Cryptococcus gattii, is causing an expanding outbreak in the Pacific Northwest that is of considerable public health impact and concern.

"This discovery of how the genome is protected during sex might be leveraged as an Achilles' heel in the battle against C. neoformans, which frequently causes life-threatening illness in people," said senior author Joseph Heitman, M.D., Ph.D., chair of the Duke Department of Molecular Genetics and Microbiology. "This protective silencing effect also operates in some animals, and our studies demonstrate that the pathway operates to defend the genome during sexual reproduction."

Sexual reproduction in fungi produces airborne spores that are readily inhaled into the lungs and thought to be the source of human infections. Thus, agents that block fungal sex might stop the risk of infection at the source.

This work was published in the Nov. 15 issue of the journal Genes & Development.

C. neoformans uses a novel sex-induced RNAi (RNA interference) genome defense system that protects by effectively "silencing" the DNA, so that it is not vulnerable to repeated genes and transposable elements that could cause mutations.

The silencing system protects the genome from changes that might be imposed by transposable elements of DNA, called "jumping genes," that are also more active during the sexual cycle, said Xuying Wang, Ph.D., a postdoctoral associate who works in the Heitman lab.

Through deep sequencing of the small RNAi pieces which mediate the silencing in C. neoformans, the team also identified abundant small RNAs which map to repetitive transposable elements that could cause mutations if not silenced.

These small RNAs were absent in mutant strains (rdp1) that were studied. One group of transposable elements was greatly expressed during mating of rdp1 mutant strains and these fungi showed an increased transposition and mutation rate in the next generation, leading the researchers to conclude that the RNAi pathway squelches transposon activity during the sexual cycle.


'/>"/>

Contact: Mary Jane Gore
mary.gore@duke.edu
919-660-1309
Duke University Medical Center
Source:Eurekalert

Related biology news :

1. Of 50,000 small molecules tested to fight cancer, 2 show promise
2. Study identifies key molecules in multiple myeloma
3. New class of biomolecules triggered in response to respiratory virus infection
4. Scientists trick bacteria with small molecules
5. MIT researchers develop a better way to see molecules at work in living brain cells
6. Scientists identify molecules involved in touch and other mechanically activated systems
7. Juelich researchers take a look inside molecules
8. Molecules delivering drugs as they walk
9. Nanoblasts from laser-activated nanoparticles move molecules, proteins and DNA into cells
10. Correcting a trick of the light brings molecules into view
11. Molecules typically found in blue jean and ink dyes may lead to more efficient solar cells
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:3/15/2016)... March 15, 2016 --> ... by Transparency Market Research "Digital Door Lock Systems Market - ... - 2023," the global digital door lock systems market in ... 2014 and is forecast to grow at a CAGR of ... small and medium enterprises (MSMEs) across the world and high ...
(Date:3/11/2016)... , March 11, 2016 ... market research report "Image Recognition Market by Technology (Pattern ... and Advertising), by Deployment Type (On-Premises and Cloud), by ... 2022", published by MarketsandMarkets, the global market is expected ... USD 29.98 Billion by 2020, at a CAGR of ...
(Date:3/9/2016)... BEACH GARDENS, Fla. , March 9, 2016 ... identity management authentication and enrollment solutions, today announced ... DigitalPersona ® Altus multi-factor authentication ... IT and InfoSec managers to step-up security where ... Washington, DC . ...
Breaking Biology News(10 mins):
(Date:5/27/2016)... ... ... Doctors in Italy, Japan, the UK and the US have reached some ... and its link to malignant mesothelioma. Surviving Mesothelioma has just posted the details of ... , The studies analyzed for the new report included more than 3,447 cancer ...
(Date:5/27/2016)... , May 27, 2016 At ... investors playing in this space know that volatility is what ... featured companies on ActiveWallSt.com: Synta Pharmaceuticals Corp. (NASDAQ: ... Lpath Inc. (NASDAQ: LPTN ), and Heat Biologics ... gain access to the technical alerts for these stocks at: ...
(Date:5/26/2016)... Jersey and READING, England ... Indegene ( http://www.indegene.com ), a leading global ... life science, pharmaceutical and healthcare organisations and TranScrip ... innovative scientific support throughout the product lifecycle, today ... the launch of IntraScience.      (Logo: ...
(Date:5/26/2016)... , May 26, 2016 Despite the ... value in this space. Today,s pre-market research on ActiveWallSt.com directs ... Health Inc. (NASDAQ: RDUS ), Cerus Corp. (NASDAQ: ... ARWR ), and Five Prime Therapeutics Inc. (NASDAQ: ... briefings at: http://www.activewallst.com/ On ...
Breaking Biology Technology: