Features | Partner Sites | Information | LinkXpress
Sign In
Demo Company

Bacterial Endonculease Complex Is a New Tool for Precise Mammalian Genome Engineering

By BiotechDaily International staff writers
Posted on 07 Feb 2013
A new tool based on endonucleases extracted from bacterial adaptive immune mechanisms that can be reprogrammed with customizable small, noncoding RNAs is beginning to be used to easily and specifically engineer the human genome.

Clustered, regularly interspaced, short palindromic repeats (CRISPR)/CRISPR-associated (Cas) systems provide adaptive immunity against viruses and plasmids in bacteria. The silencing of invading nucleic acids is executed by ribonucleoprotein complexes preloaded with small, interfering CRISPR RNAs (crRNAs) that act as guides for targeting and degradation of foreign nucleic acid.

The Cas9–crRNA complex of the Streptococcus thermophilus CRISPR3/Cas system introduces a double-strand break at a specific site in DNA containing a sequence complementary to crRNA. DNA cleavage is executed by Cas9, which uses two distinct active sites to generate site-specific nicks on opposite DNA strands. The Cas9–crRNA complex functions as an RNA-guided endonuclease with RNA-directed target sequence recognition and protein-mediated DNA cleavage.

The first description of genomic engineering using the CRISPR approach was published by investigators at the University of California, Berkeley (USA) in the August 17, 2012, issue of the journal Science. Two new papers by investigators at Harvard Medical School (Boston, MA, USA) appeared in the January 3, 2013, issue of Science and have established the concept of using CRISPR to modify the human and other mammalian genomes.

“Out of this somewhat obscure bacterial immune system comes a technology that has the potential to really transform the way that we work on and manipulate mammalian cells and other types of animal and plant cells,” said Dr. Jennifer Doudna, professor of molecular and cell biology and chemistry at the University of California, Berkeley. “This is a poster child for the role of basic science in making fundamental discoveries that affect human health. The ability to modify specific elements of an organism’s genes has been essential to advance our understanding of biology, including human health. However, the techniques for making these modifications in animals and humans have been a huge bottleneck in both research and the development of human therapeutics.

“Based on the feedback we have received, it is possible that this technique will completely revolutionize genome engineering in animals and plants,” said Dr. Doudna. “It is easy to program and could potentially be as powerful as the polymerase chain reaction (PCR).”

“I think this is going to be a real hit,” said Dr. George Church, professor of genetics at Harvard Medical School. “There are going to be a lot of people practicing this method because it is easier and about 100 times more compact than other techniques.”

Related Links:
University of California, Berkeley
Harvard Medical School



view channel
Image: A new catalyst that improved the sensitivity of the standard PSA ELISA test by about 110-fold was made of palladium nanocubes coated with iridium (Photo courtesy of Dr. Xiaohu Xia, Michigan Technological University).

Peroxidase Mimic Outperforms Natural Horseradish Peroxidase in ELISA Test

A test-of-concept study demonstrated that a synthetic catalyst that mimics the action of horseradish peroxidase (HRP) could increase the sensitivity of a colorimetric enzyme-linked immunosorbent assay... Read more

Drug Discovery

view channel
Image: Endoscopic image of a bowel section known as the sigmoid colon afflicted with ulcerative colitis. The internal surface of the colon is blotchy and broken in places (Photo courtesy of Wikimedia Commons).

Orally Delivered Curcumin-Loaded Microparticles Effectively Treat Mouse Model of Ulcerative Colitis

Microparticles (MPs) loaded with the efficient anti-inflammatory agent curcumin were found to effectively treat a mouse model of ulcerative colitis. Ulcerative colitis is a chronic relapsing disease... Read more


view channel

Biopharmaceutical Partners Seek Alternatives to Glucocorticoid Steroid Drugs

Collaboration between American and Japanese biopharmaceutical companies is expected to lead to the development of a new class of small molecule drugs for treatment of hematological and inflammatory diseases. Gencia LLC (Charlottesville, VA, USA) and Takeda Pharmaceutical Company Ltd. (Osaka, Japan) announced the formation... Read more


17 Oct 2015 - 21 Oct 2015
25 Oct 2015 - 29 Oct 2015
16 Nov 2015 - 19 Nov 2015
Copyright © 2000-2015 Globetech Media. All rights reserved.