Gene amplification is the increase in copy number of a particular piece of DNA and is a hallmark of tumor cells. Amplified genomic segments are frequently manifested in one of two cytologically recognizable forms. Double minutes are extrachromosomal segments of amplified DNA. Homogeneously staining regions are amplified intrachromosomal segments forming large genomic regions. Some strategies of pharmaceutical research in cancer prevention and treatment could involve curbing cancer development via restricting gene amplification. The first step towards achieving this is to discover the rules that govern whether an amplification event is a double minute or a homogenously-staining region.
It’s known that regions of chromosomes that are prone to amplification have palindromic sequences of DNA, which are weak places where the chromosome can break. These palindromic sequences can be naturally found in human genome. The distribution of such sequences can vary from one individual to another. Researchers at the Georgia Institute of Technology have discovered that a particular type of DNA break, a hairpin-capped double strand break, induced by these palindromic sequences, is a precursor to amplification.
“We have a developed a system in yeast which would mimic the situation in human cancer cells wherein oncogenes might be located next to palindromic sequences. Using this system we have discovered the rules that determine how double minutes or homogeneously staining regions can be generated,” said Kirill Lobachev, assistant professor in Georgia Tech’s School of Biology.
“If these rules operating in yeast can be extended to higher eukaryotes then we can propose that if the oncogene is located between the hairpin-capped break and the telomere, then the amplification event will result in a double minute. If the break occurs between the oncogene and the telomere, then the amplification would yield a homogenously-staining region.” adds Vidhya Narayanan a Ph.D. student in Kirill Lobachev’s lab and first author of the study.
The findings can help researchers understand the cause of cancer in diseased individuals and also to potentially identify individuals who might be prone for cancer.
In addition to Lobachev and Narayanan, the research team consisted of Hyun-Min Kim from Georgia Tech and collaborators Piotr A. Mieczkowski and Thomas D. Petes from Duke University. This work was supported by funds from National Science Foundation and National Institute of Health.
David Terraso | EurekAlert!
Closing in on advanced prostate cancer
13.12.2017 | Institute for Research in Biomedicine (IRB Barcelona)
Visualizing single molecules in whole cells with a new spin
13.12.2017 | Wyss Institute for Biologically Inspired Engineering at Harvard
MPQ scientists achieve long storage times for photonic quantum bits which break the lower bound for direct teleportation in a global quantum network.
Concerning the development of quantum memories for the realization of global quantum networks, scientists of the Quantum Dynamics Division led by Professor...
Researchers have developed a water cloaking concept based on electromagnetic forces that could eliminate an object's wake, greatly reducing its drag while...
Tiny pores at a cell's entryway act as miniature bouncers, letting in some electrically charged atoms--ions--but blocking others. Operating as exquisitely sensitive filters, these "ion channels" play a critical role in biological functions such as muscle contraction and the firing of brain cells.
To rapidly transport the right ions through the cell membrane, the tiny channels rely on a complex interplay between the ions and surrounding molecules,...
The miniaturization of the current technology of storage media is hindered by fundamental limits of quantum mechanics. A new approach consists in using so-called spin-crossover molecules as the smallest possible storage unit. Similar to normal hard drives, these special molecules can save information via their magnetic state. A research team from Kiel University has now managed to successfully place a new class of spin-crossover molecules onto a surface and to improve the molecule’s storage capacity. The storage density of conventional hard drives could therefore theoretically be increased by more than one hundred fold. The study has been published in the scientific journal Nano Letters.
Over the past few years, the building blocks of storage media have gotten ever smaller. But further miniaturization of the current technology is hindered by...
With innovative experiments, researchers at the Helmholtz-Zentrums Geesthacht and the Technical University Hamburg unravel why tiny metallic structures are extremely strong
Light-weight and simultaneously strong – porous metallic nanomaterials promise interesting applications as, for instance, for future aeroplanes with enhanced...
11.12.2017 | Event News
08.12.2017 | Event News
07.12.2017 | Event News
13.12.2017 | Health and Medicine
13.12.2017 | Physics and Astronomy
13.12.2017 | Life Sciences