Choice of coffee or beer can affect your DNA

December 6, 2013

DNA Jerusalem, Dec 6: Your choice of coffee or beer can not only affect your mood, but also influence a part of DNA linked to ageing and cancer, a new study claims.

Working with a kind of yeast that shares many important genetic similarities with humans, the researchers from the Tel Aviv University found that caffeine shortens and alcohol lengthens telomeres - the end points of chromosomal DNA, implicated in ageing and cancer.

"For the first time we've identified a few environmental factors that alter telomere length, and we've shown how they do it," said Professor Martin Kupiec.

"What we learned may one day contribute to the prevention and treatment of human diseases," said Kupiec. Telomeres, made of DNA and proteins, mark the ends of the strands of DNA in our chromosomes and are essential to ensuring that DNA strands are repaired and copied correctly. Every time a cell duplicates, the chromosomes are copied into the new cell with slightly shorter telomeres. Eventually, the telomeres become too short, and the cell dies. Only foetal and cancer cells have mechanisms to avoid this fate.

The researchers grew yeast cells in conditions that generate free radicals to test the effect on telomere length.

They were surprised to find that the length did not change. They went on to expose the yeast cells to 12 other environmental stressors. Most of the stressors - from temperature and pH changes to various drugs and chemicals-had no effect on telomere length.

But a low concentration of caffeine, similar to the amount found in a shot of espresso, shortened telomeres, and exposure to a 5-to-7 per cent ethanol solution lengthened telomeres.

To understand these changes, researchers scanned 6,000 strains of the yeast, each with a different gene deactivated.

They then conducted genetic tests on the strains with the longest and shortest telomeres, revealing that two genes, Rap1 and Rif1, are the main players mediating environmental stressors and telomere length.

In total, some 400 genes interact to maintain telomere length, researchers note, underscoring the importance of this gene network in maintaining the stability of the genome.

Strikingly, most of these yeast genes are also present in the human genome.

"This is the first time anyone has analysed a complex system in which all of the genes affecting it are known," said Kupiec. The study was published in the journal PLOS Genetics.

Comments

Add new comment

Coastaldigest.com reserves the right to delete or block any comments.
Coastaldigset.com is not responsible for its readers’ comments.
Comments that are abusive, incendiary or irrelevant are strictly prohibited.
Please use a genuine email ID and provide your name to avoid reject.

No evidence suggests BCG vaccine can protect against COVID-19: WHO

Agencies

April 14,2020

There is no evidence that the Bacille Calmette-Guerin (BCG) vaccine, which is primarily used against tuberculosis, protects people against infection with the novel coronavirus, the World Health Organization (WHO) said.

The WHO therefore didn't recommend BCG vaccination for the prevention of COVID-19 in the absence of evidence, according to its daily situation report on Monday, Xinhua news agency reported.

"There is experimental evidence from both animal and human studies that the BCG vaccine has non-specific effects on the immune system. These effects have not been well characterized and their clinical relevance remains unknown," WHO stated.

Two clinical trials addressing the question are underway, and WHO will evaluate the evidence when it is available, it noted.

BCG vaccination prevents severe forms of tuberculosis in children and diversion of local supplies may result in an increase of disease and deaths from the tuberculosis, it warned.

Comments

Add new comment

Coastaldigest.com reserves the right to delete or block any comments.
Coastaldigset.com is not responsible for its readers’ comments.
Comments that are abusive, incendiary or irrelevant are strictly prohibited.
Please use a genuine email ID and provide your name to avoid reject.

First open source all-atom models of COVID-19 protein developed

Agencies

June 22,2020

A team of scientists has produced first open source all-atom models of full-length COVID-19 Spike protein that facilitates viral entry into host cells – a discovery that can facilitate a faster vaccine and antiviral drug development.

The group from Seoul National University in South Korea, University of Cambridge in the UK and Lehigh University in the US produced the first open-source all-atom models of a full-length S protein.

The researchers say this is of particular importance because the S protein plays a central role in viral entry into cells, making it a main target for vaccine and antiviral drug development.

"Our models are the first full-length SARS-CoV-2 spike (S) protein models that are available to other scientists," said Wonpil Im, a professor in Lehigh University.

"Our team spent days and nights to build these models very carefully from the known cryo-EM structure portions. Modeling was very challenging because there were many regions where simple modeling failed to provide high-quality models," he wrote in a paper published in The Journal of Physical Chemistry B.

Scientists can use the models to conduct innovative and novel simulation research for the prevention and treatment of Covid-19.

Though the coronavirus uses many different proteins to replicate and invade cells, the Spike protein is the major surface protein that it uses to bind to a receptor.

The total number of global COVID-19 cases was nearing 9 million, while the deaths have increased to over 467,000, according to the Johns Hopkins University.

With 2,279,306 cases and 119,967 deaths, the US continues with the world's highest number of COVID-19 infections and fatalities, according to the CSSE.

Brazil comes in the second place with 1,083,341 infections and 50,591 deaths.

Comments