Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


A Leukemia-Related Protein is a Master Editor of the "Histone Code"


Rearrangements of the mixed lineage leukemia gene, MLL, are associated with aggressive leukemias in both children and adults. Researchers at the University of Pennsylvania School of Medicine have found that one portion of the MLL protein is an enzyme that "edits" the so-called histone code, a series of modifications to proteins associated with DNA that influence how and when certain genes are turned on and off. Their findings are presented in the November issue of Molecular Cell.

When functioning properly, the MLL protein regulates the expression of Hox genes, which play a role in cell growth and development. In some leukemias MLL is rearranged so that the cells are unable to turn off Hox genes. The Penn investigators found that a portion of the MLL protein binds directly to the Hox genes and edits the histone code at these sites. A rearranged form of MLL that causes leukemia also upregulated Hox expression but with a different "code". Presumably the differences in the pattern of histone modifications accounts for their deregulated expression in leukemia.

The histone code hypothesis was first outlined by Dr. C. David Allis and colleagues, of the University of Virginia Health System, a co-author on this paper. The theory, which rapidly is gaining acceptance, postulates that expression of certain regions of DNA is turned on and off by modifying portions of histone proteins or DNA. Modified histones and DNA attract the cell’s gene-reading machinery via specific interactions with these elements of the histone code.

According to Jay L. Hess MD, PhD, of Penn’s Department of Pathology and Laboratory Medicine and senior author of the study, these results underscore the importance of the histone code in developmental biology and disease. "Domains similar to those with histone modifying activity in MLL are found in other proteins implicated in human tumors including acute leukemia, lymphoma, and prostate cancer and probably have a similar function. What is encouraging is that proteins with enzymatic activity are good targets for drug development. These are definitely exciting times for cancer biologists."

This study was supported by grants from the Leukemia and Lymphoma Society, the National Institutes of Health, the Natural Sciences and Engineering Research Council of Canada, and the Genetics Institute of the Canadian Institute for Health Research.

Co-authors of this study include Tom Milne, Denise Gibbs, and Mary Ellen Martin, of Penn, Scott D. Briggs and C. David Allis of the University of Virginia Health System, and Hugh Brock of the University of British Columbia.

Greg Lester | EurekAlert!
Further information:

More articles from Health and Medicine:

nachricht Scientists develop tiny tooth-mounted sensors that can track what you eat
22.03.2018 | Tufts University

nachricht NIH scientists describe potential antibody treatment for multidrug-resistant K. pneumoniae
14.03.2018 | NIH/National Institute of Allergy and Infectious Diseases

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

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

Im Focus: Researchers Discover New Anti-Cancer Protein

An international team of researchers has discovered a new anti-cancer protein. The protein, called LHPP, prevents the uncontrolled proliferation of cancer cells in the liver. The researchers led by Prof. Michael N. Hall from the Biozentrum, University of Basel, report in “Nature” that LHPP can also serve as a biomarker for the diagnosis and prognosis of liver cancer.

The incidence of liver cancer, also known as hepatocellular carcinoma, is steadily increasing. In the last twenty years, the number of cases has almost doubled...

Im Focus: Researchers at Fraunhofer monitor re-entry of Chinese space station Tiangong-1

In just a few weeks from now, the Chinese space station Tiangong-1 will re-enter the Earth's atmosphere where it will to a large extent burn up. It is possible that some debris will reach the Earth's surface. Tiangong-1 is orbiting the Earth uncontrolled at a speed of approx. 29,000 km/h.Currently the prognosis relating to the time of impact currently lies within a window of several days. The scientists at Fraunhofer FHR have already been monitoring Tiangong-1 for a number of weeks with their TIRA system, one of the most powerful space observation radars in the world, with a view to supporting the German Space Situational Awareness Center and the ESA with their re-entry forecasts.

Following the loss of radio contact with Tiangong-1 in 2016 and due to the low orbital height, it is now inevitable that the Chinese space station will...

Im Focus: Alliance „OLED Licht Forum“ – Key partner for OLED lighting solutions

Fraunhofer Institute for Organic Electronics, Electron Beam and Plasma Technology FEP, provider of research and development services for OLED lighting solutions, announces the founding of the “OLED Licht Forum” and presents latest OLED design and lighting solutions during light+building, from March 18th – 23rd, 2018 in Frankfurt a.M./Germany, at booth no. F91 in Hall 4.0.

They are united in their passion for OLED (organic light emitting diodes) lighting with all of its unique facets and application possibilities. Thus experts in...

Im Focus: Mars' oceans formed early, possibly aided by massive volcanic eruptions

Oceans formed before Tharsis and evolved together, shaping climate history of Mars

A new scenario seeking to explain how Mars' putative oceans came and went over the last 4 billion years implies that the oceans formed several hundred million...

Im Focus: Tiny implants for cells are functional in vivo

For the first time, an interdisciplinary team from the University of Basel has succeeded in integrating artificial organelles into the cells of live zebrafish embryos. This innovative approach using artificial organelles as cellular implants offers new potential in treating a range of diseases, as the authors report in an article published in Nature Communications.

In the cells of higher organisms, organelles such as the nucleus or mitochondria perform a range of complex functions necessary for life. In the networks of...

All Focus news of the innovation-report >>>



Industry & Economy
Event News

Virtual reality conference comes to Reutlingen

19.03.2018 | Event News

Ultrafast Wireless and Chip Design at the DATE Conference in Dresden

16.03.2018 | Event News

International Tinnitus Conference of the Tinnitus Research Initiative in Regensburg

13.03.2018 | Event News

Latest News

Modular safety concept increases flexibility in plant conversion

22.03.2018 | Trade Fair News

New interactive map shows climate change everywhere in world

22.03.2018 | Earth Sciences

New technologies and computing power to help strengthen population data

22.03.2018 | Earth Sciences

Science & Research
Overview of more VideoLinks >>>