Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Important Human Genetic Structures Identified for the First Time

10.10.2011
Genetic information transferred within cells plays an essential role both in the healthy function of the human body and in changes within cells that can trigger serious disease.

New research led by Dmitry Temiakov, Ph.D., of UMDNJ-School of Osteopathic Medicine, has identified important mechanisms of this genetic transfer process for the first time. These new findings, published in the journal Nature, open the door to developing potential therapies for several serious diseases including cancers. They also add to basic knowledge of the functioning of the healthy human body.

Each human cell harbors small organelles called mitochondria, which are responsible for the energy production of the cell, and therefore are often called the cell’s "power plant." Mitochondria contain their own genome which is maternally inherited and encodes numerous genes of proteins that are involved in energy production. Mitochondria are also believed to fuel harmful processes that can lead to the development of conditions that include diabetes, cancer and Parkinson’s disease, as well as the onset of cognitive impairment and other conditions associated with aging.

Because of this, therapy that targets the actions of mitochondria may be a promising strategy for mitigating and even reversing these illnesses, making understanding of molecular mechanisms of mitochondrial gene expression an important goal for researchers.

The current research sought to uncover structural information about mitochondrial (human) RNA polymerase, the key enzyme in the process of transferring genetic information from mitochondrial DNA to RNA, the molecule that carries that information to structures within cells that govern those cells’ function in the body. Mitochondrial RNA polymerase does not directly share its sequence or structural homology (common evolutionary origin) with large multi-subunit cellular RNA polymerases, the variety that appears in organisms such as bacteria and also in the nuclei of human cells. The lack of commonality between two distinct varieties of polymerase that coexist within human cells has intrigued the scientific community. Thus, the structure of multi-subunit RNA polymerase II has been a subject of intensive studies, including by Nobel Laureate Roger Kornberg. In 1984 David Clayton and colleagues demonstrated that mitochondrial RNA polymerase is related to a polymerase found in a small virus of E.coli bacterium, called phage T7. This was a surprising finding since it is believed that mitochondria originated from an endosymbiotic relationship (where one organism hosts the other) formed between bacteria and eukaryotes (cells that are the building blocks of organisms that include humans) and thus that the majority of mitochondrial proteins have bacterial homologies. Until now, specific structures and pathways involved could not be identified.

The team led by Temiakov sought to make such an identification by teaming up with the lab of one of the world's leading crystallographers, Prof. Patrick Cramer in Gene Center, Munich, Germany (http://www.lmb.uni-muenchen.de/cramer/patrickCramer/index.htm). The project was initiated about four years ago but only last year the team was able to obtain large, well-diffracting crystals of an active form of human mitochondrial polymerase. The structure was solved in Cramer's lab and reveals the mechanistic adaptations that occurred during evolution of a self-sufficient T7-like RNA polymerase to become regulated by transcription initiation factors. It is the first-ever representation of mitochondrial polymerase.

Temiakov says he and his colleagues were thrilled to make their discovery. “I would compare our own excitement about this structure with what anthropologists experience when they find an ancient hominid and can see changes in the skull and other bones that occurred during an evolution and resulted in modern human beings.”

The structural information can be used to understand how mitochondrial polymerase binds DNA, interacts with other mitochondrial proteins and regulates expression of mitochondrial genes under different conditions. This knowledge will guide many future biochemical and genetic experiments and will help to validate mitochondrial polymerase as a therapeutic target.

Journalists who wish to interview Dmitry Temiakov, Ph.D., are invited to contact Rob Forman, UMDNJ Chief of News Services, at 973-972-7276 or formanra@umdnj.edu .

The University of Medicine and Dentistry of New Jersey (UMDNJ) is the nation's largest free-standing public health sciences university with more than 6,000 students on five campuses attending the state's three medical schools, its only dental school, a graduate school of biomedical sciences, a school of health related professions, a school of nursing and New Jersey’s only school of public health. UMDNJ operates University Hospital, a Level I Trauma Center in Newark, and University Behavioral HealthCare, which provides a continuum of healthcare services with multiple locations throughout the state.

Rob Forman | Newswise Science News
Further information:
http://www.umdnj.edu

More articles from Life Sciences:

nachricht Newly designed molecule binds nitrogen
23.02.2018 | Julius-Maximilians-Universität Würzburg

nachricht Atomic Design by Water
23.02.2018 | Max-Planck-Institut für Eisenforschung GmbH

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Attoseconds break into atomic interior

A newly developed laser technology has enabled physicists in the Laboratory for Attosecond Physics (jointly run by LMU Munich and the Max Planck Institute of Quantum Optics) to generate attosecond bursts of high-energy photons of unprecedented intensity. This has made it possible to observe the interaction of multiple photons in a single such pulse with electrons in the inner orbital shell of an atom.

In order to observe the ultrafast electron motion in the inner shells of atoms with short light pulses, the pulses must not only be ultrashort, but very...

Im Focus: Good vibrations feel the force

A group of researchers led by Andrea Cavalleri at the Max Planck Institute for Structure and Dynamics of Matter (MPSD) in Hamburg has demonstrated a new method enabling precise measurements of the interatomic forces that hold crystalline solids together. The paper Probing the Interatomic Potential of Solids by Strong-Field Nonlinear Phononics, published online in Nature, explains how a terahertz-frequency laser pulse can drive very large deformations of the crystal.

By measuring the highly unusual atomic trajectories under extreme electromagnetic transients, the MPSD group could reconstruct how rigid the atomic bonds are...

Im Focus: Developing reliable quantum computers

International research team makes important step on the path to solving certification problems

Quantum computers may one day solve algorithmic problems which even the biggest supercomputers today can’t manage. But how do you test a quantum computer to...

Im Focus: In best circles: First integrated circuit from self-assembled polymer

For the first time, a team of researchers at the Max-Planck Institute (MPI) for Polymer Research in Mainz, Germany, has succeeded in making an integrated circuit (IC) from just a monolayer of a semiconducting polymer via a bottom-up, self-assembly approach.

In the self-assembly process, the semiconducting polymer arranges itself into an ordered monolayer in a transistor. The transistors are binary switches used...

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...

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

A Keen Sense for Molecules

23.02.2018 | Physics and Astronomy

“Laser Technology Live” at the AKL’18 International Laser Technology Congress in Aachen

23.02.2018 | Trade Fair News

Newly designed molecule binds nitrogen

23.02.2018 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>