Histone modification controls development: Researchers demonstrate that chemical tags on histones regulate gene activity

Feb 11, 2013

Every gene in the nucleus of an animal or plant cell is packaged into a beads-on-a-string like structure called nucleosomes: the DNA of the gene forms the string and a complex of proteins called histones forms the beads around which the DNA is wrapped.

Scientists of the Institute of Biochemistry in Martinsried near Munich, Germany, have now established that adding chemical tags on histones is critical for regulating during . Studies over the past two decades revealed that many proteins that control the activity of genes are enzymes that add small chemical tags on but also on a variety of other proteins. With their studies the researchers have now shown that it is the tags on the histones that control if genes are active or inactive. Their results were published in the journal Science.

Histone proteins can be modified by a number of different chemical tags at very specific sites. The researchers in the Research Group 'Chromatin Biology' of Jürg Müller focused on the histone tag that is added by an enzyme called Polycomb Repressive Complex 2 (PRC2). PRC2 is essential for a variety of different cell fate decisions in animals and plants. PRC2 functions to keep genes inactive in cells and at times where they should remain inactive.

Using the Drosophila - the fruit fly - the scientists now generated animals with cells expressing an altered histone protein to which PRC2 can no longer add the tag. These cells cannot keep genes inactive anymore and many cell fate decisions go awry, exactly like in cells that lack the PRC2 enzyme. "This observation demonstrates that the business end is the tag on the histone and not on some other protein" says Ana Pengelly, the PhD student who conducted the experiments. Her colleague Omer Copur adds: "The approach we used permits us to now also investigate the function of other tags on histone proteins that have a different chemical nature." The insight gained from the work on PRC2 provides a strong impetus to figure how this tag alters the beads-on-a-string structure of genes and thereby controls gene activity.

Explore further: The origin of the language of life

More information: Pengelly, A.R., et al. A histone mutant reproduces the phenotype caused by loss of histone modifying factor Polycomb. Science, February 8, 2013.
DOI: 10.1126/science.1231382

add to favorites email to friend print save as pdf

Related Stories

How the wrong genes are repressed

Jun 11, 2010

The mechanism by which 'polycomb' proteins critical for embyronic stem cell function and fate are targeted to DNA has been identified by UCL scientists.

Scientists discover secret life of chromatin

Sep 01, 2011

Chromatin - the intertwined histone proteins and DNA that make up chromosomes – constantly receives messages that pour in from a cell’s intricate signaling networks: Turn that gene on. Stifle that one.

Jarid2 may break the Polycomb silence

Apr 30, 2012

Historically, fly and human Polycomb proteins were considered textbook exemplars of transcriptional repressors, or proteins that silence the process by which DNA gives rise to new proteins. Now, work by a ...

Recommended for you

The origin of the language of life

11 hours ago

The genetic code is the universal language of life. It describes how information is encoded in the genetic material and is the same for all organisms from simple bacteria to animals to humans. However, the ...

Quest to unravel mysteries of our gene network

Dec 18, 2014

There are roughly 27,000 genes in the human body, all but a relative few of them connected through an intricate and complex network that plays a dominant role in shaping our physiological structure and functions.

EU court clears stem cell patenting

Dec 18, 2014

A human egg used to produce stem cells but unable to develop into a viable embryo can be patented, the European Court of Justice ruled on Thursday.

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.