Navigation Links
Brown-Harvard team solves mobile DNA's surgical sleight-of-hand

In a clever bit of biology called site-specific recombination, DNA can travel inside an organism, or into another organism, and perform a sort of grafting surgery that allows it to insert its chromosome into a chromosome of the target cell. The process is important because mobile DNA can carry genes that cause drug resistance or transmit viruses that cause disease or tumors that result in certain leukemias or other cancers.

But what do the surgeons look like that conduct these intricate snip-and-solder procedures?

While scientists have studied site-specific recombination for about 30 years, much remains a mystery. In the current issue of Nature, a Brown University and Harvard Medical School team reveals the crystal structure of λ-integrase (λ-INT), the protein responsible for this DNA doctoring in the lambda virus, which infects and lives off Escherichia coli (E. coli) bacteria.

The findings are important because lambda is a model virus used to understand mobile DNA, according to Arthur Landy, professor of medical science in the Department of Molecular Biology, Cell Biology and Biochemistry at Brown. "Once you see the parts and how they fit together, you have a much better understanding of how the process works," Landy said. "So this work represents a major leap."

When the lambda virus inserts its DNA into E. coli, λ-INT is the major player in the process, literally snipping the E. coli DNA strands before insertion and then sealing them up afterward. The research also suggests how three "helper" proteins ?think of them as nurses ?intricately fold the DNA strands during this surgery.

Marta Radman-Livaja, a postdoctoral research associate at Brown, conducted the biological and biochemical aspects of the experiments. The Harvard team ?Tapan Biswas, Hideki Aihara, David Filman and Tom Ellenberger ?used X-ray crystallography, a technique that combines strong X-rays and sophisticated computer software, to create a 3-D digital image o f λ-INT caught in the act of carrying out site-specific recombination.

In complementary experiments carried out at Brown and published recently in the Proceedings of the National Academy of Sciences, Radman-Livaja tagged bits of lambda DNA with dyes that allowed her to draw up a map of this viral DNA during insertion.

"It was gratifying to see that two totally different experimental approaches give the same picture," Radman-Livaja said. "It means we have a very solid foundation for the next step forward in understanding this fascinating process."


'"/>

Source:Brown University


Related biology news :

1. NASA study solves ocean plant mystery
2. Insight into DNAs weakest links may yield clues to cancer biology
3. Uncovering DNAs sweet secret
4. “Nano-scissors?laser shows precise surgical capability
Post Your Comments:
*Name:
*Comment:
*Email:


(Date:4/15/2016)... , April 15, 2016 ... "Global Gait Biometrics Market 2016-2020,"  report to their ... ) , ,The global gait biometrics market ... 13.98% during the period 2016-2020. Gait ... which can be used to compute factors that ...
(Date:4/13/2016)... , April 13, 2016  IMPOWER physicians supporting Medicaid ... setting a new clinical standard in telehealth thanks to ... leveraging the higi platform, IMPOWER patients can routinely track ... and body mass index, and, when they opt in, ... convenient visit to a local retail location at no ...
(Date:3/31/2016)... R.I. , March 31, 2016  Genomics firm ... of founding CEO, Barrett Bready , M.D., who ... members of the original technical leadership team, including Chief ... President of Product Development, Steve Nurnberg and Vice President ... returned to the company. Dr. Bready served ...
Breaking Biology News(10 mins):
(Date:6/24/2016)... ... 24, 2016 , ... While the majority of commercial spectrophotometers and fluorometers use ... 6000i models are higher end machines that use the more unconventional z-dimension of 20mm. ... from the bottom of the cuvette holder. , FireflySci has developed several Agilent ...
(Date:6/23/2016)... June 23, 2016   Boston Biomedical , ... compounds designed to target cancer stemness pathways, announced ... granted Orphan Drug Designation from the U.S. Food ... gastric cancer, including gastroesophageal junction (GEJ) cancer. Napabucasin ... to inhibit cancer stemness pathways by targeting STAT3, ...
(Date:6/23/2016)... ... June 23, 2016 , ... ... and Mold) microbial test has received AOAC Research Institute approval 061601. , “This ... introduced last year,” stated Bob Salter, Vice President of Regulatory and Industrial Affairs. ...
(Date:6/23/2016)... ... 2016 , ... Supplyframe, the Industry Network for electronics hardware ... . Located in Pasadena, Calif., the Design Lab’s mission is to bring together ... built and brought to market. , The Design Lab is Supplyframe’s physical representation ...
Breaking Biology Technology: