Scientists zoom in to see the DNA code being read

The mechanism by which the DNA is read and decoded into the protein that meets its needs is common to all animals and plants and is often hijacked by cancer.

The researchers used a high-level electron microscope called Cryo-EM, which was awarded to the Nobel Prize in 2017 for magnification and capture of the reading mechanism's image with unprecedented detail.

The exact discovery of this molecular mechanism, published in the journal Nature, may open up new avenues for cancer treatment.

Scientists at the London Cancer Institute have captured the images of a molecular machine called RNA polymerase III that transcribes a gene in a subtle and unprecedented detail.

This work is funded by the Biotechnology and Biological Sciences Research Council (BBSRC), the British Cancer Research Center and Wellcome Trust.

RNA polymerase III is crucial for the life of all eukaryotic cells, including all animals and plants. In cancer, it is more active, resulting in cells producing more components that need to grow and reproduce.

Cryo-EM is so powerful that it can shoot tiny molecules at the atomic level - about 5 nanometers or 20,000 times the width of a human hair.

For the first time, researchers found out how RNA polymerase III complexes interacted with accessory ancillary molecules and proposed ways to use the drug to break down the complex.

The new study captures the molecular mechanics of DNA-binding behavior by separating the two strands and preparing the transcriptional DNA.

Cryo-electron microscopy includes freezing and imaging samples at a temperature of -180 ° C to preserve the fine details of the protein shape. This type of microscope is also an emerging and exciting approach to cancer drug design.

Using this technology, scientists at the Institute for Cancer Research (ICR) have uncovered five key phases in which complex recombination itself successfully transcribed the DNA code. Each of these phases is likely to be the target of a new drug.

Researchers have studied the molecular mechanisms of yeast cells, but the same mechanism has been used in humans.

This complex process reads the DNA code and calls the RNA-transferring material "transfer RNA" - a key part of the building blocks of proteins needed to make cells grow or create new cells.

Tumor cells require a large number of protein building blocks during rapid growth and division and therefore they may depend in particular on the composition of the RNA polymerase III complex.

Dr Alessandro Vannini, head of structural biology at the Institute of Cancer Research in London, said: "We used a very exciting new microscopy called cryogenic microscopy that scientists have never done before We were able to freeze and capture the RNA polymerase III complex, connecting, isolating and reading the DNA code, we got nearly 1 million snapshots and used a powerful computer to combine similar snapshots Together, their details were enhanced, and the machine was vividly rebuilt at work. "

"Now that we know how the components of this key molecular mechanism are integrated, we might be able to design drugs that turn the system on and off - these drugs could provide a whole new way of treating cancer."

Professor Paul Workman, chief executive of the Institute of Cancer Research in London, said: "Cryo-EM is revolutionizing molecular and cell biology, enabling us to examine in detail the intracellular molecular machinery for minute details and how they are The technology is helping scientists spot weak spots in cancer cells that could potentially target the next generation of drugs. "

"This beautiful study reveals that a fundamental gear that works inside a cell is often exploited by cancer.This is an extremely important discovery in cell biology and I hope it will bring new treatments to cancer patients in the future "

Dr. Amanda Collis, Interim Executive Director of the BBSRC Science Department, said: "Cryo-EM is rapidly raising our awareness of the structure and behavior of biomolecules and this exciting discovery demonstrates how a fundamental understanding of biological systems is potentially new The development of cancer therapies opens the door. "

Sam Gyimah, University and Science Minister, said: "This incredible new advance in DNA decoding will facilitate our understanding of the disease and may lead to critical life-saving treatments, including new ways to deal with cancer.

"Through our industrial strategy, the recently published Life Sciences Sectors Agreement will pave the way for more new investments in innovative therapies and technologies that will not only improve the lives of patients, but will also fuel British economic growth by Suitable for the future. "

This article is from [GED ChemNet], Original: http://news.china.guidechem.com/2018/01/19/308355.html