Navigation Links
Nanoscale microscope sheds first light on gene repair

Proteins called H2AX act as "first aid" to DNA, among other roles. For the first time, scientists using the world's most powerful light microscope (the only one of its kind in the Americas) have seen how H2AX is distributed in the cell nucleus: in clusters, directing the first aid/repair after DNA injuries to the region where it is really needed.

Many biological processes lie out of the visual reach of scientists. The benefits of high-resolution electron microscopy are often offset by disruptive sample preparation requirements. Light microscopy allows easier sample prep and observations of living cells, but it has limited resolution. By manipulating how light waves behave, however, biophysicists are expanding the limits of light microscopy, and one of the latest advances--the 4Pi microscope--provides never-before-seen views of cellular components, including structures within the nucleus.

In a paper published in the Proceedings of the National Academy of Sciences, Joerg Bewersdorf of the Institute for Molecular Biophysics at The Jackson Laboratory, with collaborators Brian Bennett of the UMass Medical School and Leica Microsystems and Kendall Knight of the UMass Medical School, used the 4Pi microscope to examine the cellular response to a type of severe damage to the genetic material, DNA double-strand breaks. Such breaks provoke a rapid and highly coordinated series of events to identify and repair the damage. The response is critical, and there is an increased risk for cancer, developmental abnormalities and immunological problems when components of the repair processes are defective.

Traditional microbiological and genetics techniques can shed light on the molecular pathways of repair, but they don't address the astonishingly complex three-dimensional structure of the genetic material in the nucleus. 4Pi microscopy allows researchers to actually see the response in three dimensions, at resolutions down to 100 nm. Therefore, the r ole of the physical structures in various processes within the nucleus can now be visualized.

"The general application of these methods will provide unprecedented insights into cellular molecular events," said Bewersdorf. "This study represents a significant advance in our ability to visualize and quantify nuclear proteins in 3D."

Bewersdorf, Bennett and Knight examined a protein called H2AX, a kind of histone. Histones are structural proteins that act as spools around which DNA is wound, and they can also play roles in gene regulation and gene repair. H2AX is an early responder to DNA damage, and its change to what is known as gamma-H2AX is important for the coordination of signaling and repair activities. But it had not been known how H2AX is distributed throughout the nucleus or why its conversion to gamma-H2AX is limited to within a short distance of a break site. By using selective staining techniques and 4Pi visualization, Bewersdorf and colleagues determined that H2AX is distributed in distinct clusters uniformly throughout the nucleus and that the structure of these clusters may determine the boundaries of where gamma-H2AX spreads in response to a break.

"The clusters may provide a platform for the immediate and robust response observed following DNA damage," said Bewersdorf. "Moving forward, we will analyze the localization of the H2AX clusters relative to other nuclear components."

Source:Jackson Laboratory

Related biology news :

1. Nanoscale Diagnostic Sets Sights on Alzheimers
2. Nanoscale method for investigating living systems
3. New, unique microscope for nanotech
4. High-resolution light microscope reveals the fundamental mechanisms of nerve communication
5. New light microscope sharpens scientists focus
6. Bacteria collection sheds light on urinary tract infections
7. Sea skate experiment sheds light on human cell transport
8. Bacterial genome sheds light on synthesizing cancer-fighting compounds
9. Newly discovered genetic disease sheds light on bodys water balance
10. Multi-species genome comparison sheds new light on evolutionary processes, cancer mutations
11. Gene discovery sheds light on causes of rare disease, cancer

Post Your Comments:

(Date:11/16/2015)... 2015  Synaptics Inc. (NASDAQ: SYNA ), ... announced expansion of its TDDI product portfolio with ... and display driver integration (TDDI) solutions designed to ... TDDI products add to the previously-announced TD4300 ... resolution), and TD4322 (FHD resolution) solutions. All four ...
(Date:11/11/2015)... 11, 2015   MedNet Solutions , an innovative SaaS-based ... research, is pleased to announce that it will be a ... event, to be held November 17-19 in ... live demonstrations of iMedNet , MedNet,s easy-to-use, ... iMedNet has been able to deliver time and cost ...
(Date:11/9/2015)... , Nov. 9, 2015  Synaptics Inc. (NASDAQ: ... today announced broader entry into the automotive market with ... match the pace of consumer electronics human interface innovation. ... are ideal for the automotive industry and will be ... Europe , Japan ...
Breaking Biology News(10 mins):
(Date:11/24/2015)... QUEBEC CITY , Nov. 24, 2015 /PRNewswire/ - ... the request of IIROC on behalf of the Toronto ... this news release there are no corporate developments that ... price. --> --> ... --> . --> Aeterna Zentaris ...
(Date:11/24/2015)... Muncie, IN (PRWEB) , ... November 24, 2015 , ... ... its newest Special Interest Group (SIG), MultiGP, also known as Multirotor Grand Prix, to ... in the last few years. Many AMA members have embraced this type of racing ...
(Date:11/24/2015)... 2015 /PRNewswire/ - Aeterna Zentaris Inc. (NASDAQ:  AEZS) ... remaining 11,000 post-share consolidation (or 1,100,000 pre-share consolidation) ... B Warrants") subject to the previously disclosed November ... 2015, which will result in the issuance of ... the issuance of such shares, there will be ...
(Date:11/24/2015)... ... November 24, 2015 , ... Creation Technologies would ... named to Deloitte's 2015 Technology Fast 500 list of the fastest growing companies ... FDA-cleared, Class II medical device that speeds up orthodontic tooth movement by as ...
Breaking Biology Technology: