||Dr. Carolyn Larabell of Lawrence Berkeley National Laboratory shows Dr. Elias Zerhouni one of the features of the new X-ray microscope.
NIH director Dr. Elias Zerhouni had a chance to return to his professional roots during a recent visit to the Lawrence Berkeley National Laboratory-
home to a one-of-a-kind microscope that uses X-rays to peer inside cells.
Dr. Graham Fleming, Berkeley lab deputy director,
took Zerhouni on a tour of the advanced light source facility, a national resource that generates extremely bright light for use in scientific
and technological research. Zerhouni
stopped at two places during the tour: the Berkeley Center for Structural Biology, a facility dedicated to determining the crystal structures of proteins, and the National Center for X-ray Tomography.
The latter facility, developed with support from NIH's National Center for Research Resources as well as the Department of Energy, houses the first microscope able to image molecules inside cells using X-rays. Just as CAT (computerized axial tomography) scans provide three-dimensional
images of structures inside the human body, this new microscope can generate high-fidelity images of structures inside cells. The microscope uses powerful X-rays created by the Berkeley lab's synchrotron-an instrument that produces beams much brighter than those from laboratory X-ray generators.
Zerhouni, a radiologist with considerable experience
in full-body CAT scanning, was enthusiastic
about the potential of the new technique. "He instantly understood what we were doing, why we were doing it and why it was important," said Dr. Carolyn Larabell, principal investigator at the cent
er. Although other powerful microscopes can generate images of cells, the new microscope,
which Larabell helped design, is ideal for determining the position of proteins and other molecules inside cells.
In addition, the microscope does its job extremely
quickly and with greater precision than other high-power microscopes. For example, the cell nucleus, the part of the cell that holds its genetic material, has been very difficult to study with traditional methods. "The nucleus is a black box in many ways," explained Larabell. "Many sub-compartments have been identified inside the nucleus, but now we can begin to look precisely at how they are organized."
NCRR started funding the National Center for X-ray Tomography 3 years ago when scientists there began designing and constructing the new microscope. The facility officially opened in January
2007 as one of 51 NCRR-funded Biomedical
Technology Research Resources around the nation that develop a broad spectrum of new technologies and methodologies and provide scientists with training in and access to these technologies. Researchers may use the new X-ray microscope and other resources at the center
by submitting a proposal at http://ncxt.lbl.gov. Several companies have also started designing
table-top versions of the microscope, which should be available to researchers in the next 3 to 5 years.