Scientists test commonly used antibodies

Dec 06, 2010

If a strand of your DNA was stretched out completely, it would be more than six feet long. It's hard to imagine that it can fit inside the nucleus of one of your cells, but that's exactly how it works.

For much of the last century, scientists have been busy figuring out how is packaged in , and have found strong indications that the packaging is integral to how DNA works. The packaging – comprised mostly of an amino acid molecule called a histone – influences the on and off switches of different genes that regulate cellular function and play a role in human diseases ranging from cancer to genetic disorders. Scientists study histones by using to specific "flavors" of histones that are only very slightly different from one another. The antibodies help to pinpoint what DNA is being packaged by a certain kind of "flavor" of histone, and how that affects gene regulation. Different flavors affect genes differently.

"And this is where it gets complicated," says Jason Lieb, PhD, who led the project. "Many companies make these antibodies that we scientists use in our labs – but there are so many different kinds of histones and types of tests we do that it's just not feasible for the companies to anticipate every single way that a given antibody can be used."

This is a problem, explains Lieb, who is a professor of biology at UNC-Chapel Hill and member of UNC Lineberger Comprehensive Cancer Center, since scientists can't be absolutely certain that the antibody is recognizing a specific "flavor" of histone, or one that is very closely related.

"Histones are essentially the key to the DNA library. They tell you which 'shelves' of that library – or areas of the genome – are open or closed to information moving in and out. But since the differences between the different 'flavors' of histones are often extremely small, and it's likely that an antibody may react with more than one histone or in different ways depending on the type of test being used in the lab. It makes scientific precision very difficult," Lieb notes.

In a paper published today in the journal , Lieb and his colleagues from across the country describe how they tested more than 200 antibodies against 57 histone modifications (or flavors) in three different organisms, using three different tests commonly used in this kind of genetic analysis. They found that about 25 percent of antibodies currently sold have a problem with specificity – targeting the anticipated histone – in a given test. They believe that this proportion is likely to remain steady over time.

"So we thought, ok, we need to help ourselves as scientists. We set up a web-based searchable database at http://compbio.med.harvard.edu/antibodies. Our results are there and other scientists can also post their results so that we have a self-sustaining, up-to-date source of information that is really important to scientists working to understand a broad range of genetic phenomena," he said.

Explore further: Toxin targets discovered

More information: www.nature.com/nsmb/index.html

Related Stories

Histone modifications control accessibility of DNA

Jul 14, 2010

(PhysOrg.com) -- n an advanced online publication in Nature Structural & Molecular Biology scientist from Dirk Schübeler's group from the Friedrich Miescher Institute for Biomedical Research provide a geno ...

Roles of DNA packaging protein revealed

Feb 12, 2009

Scientists at Albert Einstein College of Medicine of Yeshiva University have found that a class of chromatin proteins is crucial for maintaining the structure and function of chromosomes and the normal development ...

On the trail of the epigenetic code

Oct 11, 2010

The genetic inherited material DNA was long viewed as the sole bearer of hereditary information. The function of its packaging proteins, the histones, was believed to be exclusively structural. Additional ...

Messenger RNA with FLASH

Oct 22, 2009

A study from the University of North Carolina at Chapel Hill has identified a key player in a molecular process essential for DNA replication within cells.

Recommended for you

Toxin targets discovered

4 hours ago

Research that provides a new understanding of how bacterial toxins target human cells is set to have major implications for the development of novel drugs and treatment strategies.

New method for quickly determining antibiotic resistance

11 hours ago

Scientists from Uppsala University, the Science for Life Laboratory (SciLifeLab) in Stockholm and Uppsala University Hospital have developed a new method of rapidly identifying which bacteria are causing an infection and ...

Cohesin molecule safeguards cell division

Nov 21, 2014

The cohesin molecule ensures the proper distribution of DNA during cell division. Scientists at the Research Institute of Molecular Pathology (IMP) in Vienna can now prove the concept of its carabiner-like ...

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.