Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

The Wider View from a Detailed Focus: New Project challenges conventional view of genome biology

14.06.2007
A major study of the organization and regulation of the human genome published today changes our concept of how our genome works. The integrated study is an exhaustive analysis of 1% of the genome that, for the first time, gives an extensive view of genetic activity alongside the cellular machinery that allows DNA to be read and replicated.

The lead report from the ENCyclopedia Of DNA Elements (ENCODE) Consortium, published in Nature, together with 28 companion papers published in Genome Research, defined in detail which regions of the genome are actively copied in the cell, revealed the location and studied evolution of elements that control gene activity, and defined the relationship between DNA-associated proteins and gene activity and DNA replication.

The complex tapestry of interwoven elements revealed today suggests that "our perspective of transcription and genes may have to evolve," the researchers state, noting that their research "poses some interesting mechanistic questions" that have yet to be answered.

Our understanding of genome biology from the Human Genome Project gave us an overview of a 3-billion-base genome, peppered with some 22,000 discrete genes and the sequences that regulate their activity. These were estimated to occupy perhaps 3-5% of the genome, though this number is expected to be an underestimate.

... more about:
»Cell »DNA »DNA sequence »ENCODE »Genom »Regulation »transcription

"The new view transforms our view of the genomic fabric," explained Dr Tim Hubbard, from the Wellcome Trust Sanger Institute, "The majority of the genome is copied, or transcribed, into RNA, which is the active molecule in our cells, relaying information from the archival DNA copy to the cellular machinery. This is a remarkable finding, since most prior research suggested only a fraction of the genome was transcribed."

"But it is our new understanding of regulation of genes that stands out. The integrated approach has helped us to identify new regions of gene regulation and altered our view of how gene regulation occurs."

From the earliest studies of gene activity in bacteria, a picture emerged that suggested control regions were most often located at or near sites from which gene transcription started. The new work identifies many previously unknown control regions and shows that control regions are as likely to be beyond the end of the gene.

Alterations in control regions are increasingly thought to be of significance for human disease, Dr Dermitzakis from the Wellcome Trust Sanger Institute and one of the corresponding authors on the paper explained: "For the first time we can see DNA sequence variation in the context of the biochemical workings of the cell. We can now begin to unravel the consequences that such variations hold for individuals and their susceptibility to disease."

The team showed that transcription of DNA is pervasive across the genome, and that RNA transcripts overlap known genes and are found in what were previously thought to be gene ‘deserts'.

"A major surprise was that many of the novel control regions are not shared with other species, but restricted to our human genome," continued Dr Dermitzakis. "We appear to have a reservoir of active elements that seem to provide no specific or direct benefit.

"Our suggestion is that these elements can provide a source for new variation between species and within the human genome. This is our genomic seedcorn for the future. "

The scale of the collaboration brings new understanding of the interaction between our genome and the proteins that control gene activity and DNA replication. The results show that proteins called histones that bind DNA to package it within the cell nucleus are modified to promote or inhibit gene activity and can be used to predict better the location of novel genes.

"Specific types of modifications of the histone proteins near gene starts are a strong predictor of gene activity," explained Dr Ian Dunham, from the Wellcome Trust Sanger Institute, "whereas further histone modifications at sites away from genes appear to be a signature of regulatory elements that can enhance transcription." A detailed analysis of these effects is also published by the Sanger Institute group in one of the companion papers in Genome Research.

"It is only from a study such as ENCODE that we can obtain such a valuable detailed view of our genome. This project has been a magnificent collaboration amongst some of the world's premier genome scientists, and has revealed many new insights. There is every expectation that a great deal more will be revealed as the project scales to the whole genome."

Although much that is new has been discovered, much yet remains to be understood. Similarity of DNA sequence between species is often a sign of the value of that sequence, yet a function has not been found for many DNA sequences that are conserved. The role of the massive new numbers of RNA transcripts is unknown. And the function of the large number of control elements is yet to be elucidated.

The ENCODE consortium is organized by the National Human Genome Research Institute (NHGRI), whose Director, Francis S Collins, MD PhD, said: "This impressive effort has uncovered many exciting surprises and blazed the way for future efforts to explore the functional landscape of the entire human genome.

"Because of the hard work and keen insights of the ENCODE consortium, the scientific community will need to rethink some long-held views about what genes are and what they do, as well as how the genome's functional elements have evolved. This could have significant implications for efforts to identify the DNA sequences involved in many human diseases."

Don Powell | alfa
Further information:
http://www.sanger.ac.uk

Further reports about: Cell DNA DNA sequence ENCODE Genom Regulation transcription

More articles from Life Sciences:

nachricht At last, butterflies get a bigger, better evolutionary tree
16.02.2018 | Florida Museum of Natural History

nachricht New treatment strategies for chronic kidney disease from the animal kingdom
16.02.2018 | Veterinärmedizinische Universität Wien

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Demonstration of a single molecule piezoelectric effect

Breakthrough provides a new concept of the design of molecular motors, sensors and electricity generators at nanoscale

Researchers from the Institute of Organic Chemistry and Biochemistry of the CAS (IOCB Prague), Institute of Physics of the CAS (IP CAS) and Palacký University...

Im Focus: Hybrid optics bring color imaging using ultrathin metalenses into focus

For photographers and scientists, lenses are lifesavers. They reflect and refract light, making possible the imaging systems that drive discovery through the microscope and preserve history through cameras.

But today's glass-based lenses are bulky and resist miniaturization. Next-generation technologies, such as ultrathin cameras or tiny microscopes, require...

Im Focus: Stem cell divisions in the adult brain seen for the first time

Scientists from the University of Zurich have succeeded for the first time in tracking individual stem cells and their neuronal progeny over months within the intact adult brain. This study sheds light on how new neurons are produced throughout life.

The generation of new nerve cells was once thought to taper off at the end of embryonic development. However, recent research has shown that the adult brain...

Im Focus: Interference as a new method for cooling quantum devices

Theoretical physicists propose to use negative interference to control heat flow in quantum devices. Study published in Physical Review Letters

Quantum computer parts are sensitive and need to be cooled to very low temperatures. Their tiny size makes them particularly susceptible to a temperature...

Im Focus: Autonomous 3D scanner supports individual manufacturing processes

Let’s say the armrest is broken in your vintage car. As things stand, you would need a lot of luck and persistence to find the right spare part. But in the world of Industrie 4.0 and production with batch sizes of one, you can simply scan the armrest and print it out. This is made possible by the first ever 3D scanner capable of working autonomously and in real time. The autonomous scanning system will be on display at the Hannover Messe Preview on February 6 and at the Hannover Messe proper from April 23 to 27, 2018 (Hall 6, Booth A30).

Part of the charm of vintage cars is that they stopped making them long ago, so it is special when you do see one out on the roads. If something breaks or...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

2nd International Conference on High Temperature Shape Memory Alloys (HTSMAs)

15.02.2018 | Event News

Aachen DC Grid Summit 2018

13.02.2018 | Event News

How Global Climate Policy Can Learn from the Energy Transition

12.02.2018 | Event News

 
Latest News

Fingerprints of quantum entanglement

16.02.2018 | Information Technology

'Living bandages': NUST MISIS scientists develop biocompatible anti-burn nanofibers

16.02.2018 | Health and Medicine

Hubble sees Neptune's mysterious shrinking storm

16.02.2018 | Physics and Astronomy

VideoLinks
Science & Research
Overview of more VideoLinks >>>