GRK2 enzyme
helps keep
G proteins at bay
by Art Robinson
G proteins in the cell serve as molecular
switches for important signaling cascades, including those
that control heart rate, blood pressure, and glucose metabolism
and those that mediate the senses of taste, smell, and vision.
The G proteins themselves are activated by G-protein-coupled
receptors (GPCRs), which reside in the cell membrane and react
to specific external signals, such as light or adrenaline.
In order for cells to adapt to changes in their external (extracellular)
environments, activated GPCRs must be rapidly desensitized.
This process is initiated by G-protein-coupled receptor kinases
(GRKs), enzymes that phosphorylate (add phosphate groups to)
the portions of activated GPCRs that project into the cell.
To study this mechanism at the molecular level, a collaboration
from the University of Texas and the Duke University Medical
Center has determined the crystal structure of a form of GRK
in complex with portions of its target molecule.
Full story.
Publication about this research: D.T. Lodowski,
J.A. Pitcher, W.D. Capel, R.J. Lefkowitz, J.J.G. Tesmer,
"Keeping G proteins at bay: A complex between G
protein-coupled receptor kinase 2 and G-beta-gamma,"
Science 300, 1256 (2003).
Contacts: David Lodowksi, dave@icmb.utexas.edu;
John Tesmer, tesmer@mail.utexas.edu
SAC memebers
focus on ALS
upgrade, new directions
The Scientific Advisory Committee (SAC)
met on December 16–17 with a full and exciting agenda.
Neville Smith (ALS Division Deputy for Science) began the
meeting with an update on ALS operations and productivity.
David Robin (Accelerator Physics Group Leader) and Tony Warwick
(Experimental Systems Group) spoke about the proposed ALS
upgrade. John Kinney (LLNL) spoke about the new tomography
beamline (8.3.2) and the wide range of interesting experiments
that beamline will accommodate. Paul Alivisatos (UC Berkeley)
spoke about the new beamline for high-pressure research (12.2.2).
A large user community is anticipated for this beamline and
groups, such as CALIPSO, have already been quite active in
planning an array of experiments. Steve Leone (UC Berkeley)
gave an update on work at the chemical dynamics beamline (9.0.2)
and indicated the new directions the group will be taking
in the future, such as creating more mobile endstations so
that groups can use other beamlines along with 9.0.2 for their
experiments. Closing out the first day of the meeting, John
Spence (Arizona State Univ.) spoke about lensless imaging
at Beamline 9.0.1. On December 17, the meeting continued
with Miguel Salmeron (Berkeley Lab) talking about the Molecular
Foundry construction, proposal process, and an upcoming
science workshop.
The meeting agenda concluded with talks
by Ben Feinberg on radioactive-sample policy at the ALS, Zahid
Hussain on the ALS
Doctoral Fellowship Program, and by Yves Idzerda (chair
of the Proposal Study Panel) on approved-program
status. A close-out session followed with a brief summary
given by the SAC chair, Sam Bader (Argonne). Current members
of the advisory committee are listed
online.
Contact: Neville Smith, NVSmith@lbl.gov
Free SXR/EUV
lectures
Webcast live
"Soft X-Rays and Extreme Ultraviolet Radiation,"
a course being taught by David Atwood at UC Berkeley this
spring, is being Webcast live over the Internet on Tuesdays
and Thursdays from January 20 to May 14, 2004. The
course Web
page includes links to the webcasts, handouts, and homework
problems. The lectures begin at approximately 2:10 P.M.
(Pacific time); completed lectures will be archived to allow
for later viewing. The Webcasts are free, sponsored in part
by the National Science Foundation.
The course will explore modern developments
in the physics and applications of soft x rays and extreme
ultraviolet radiation. Following a brief review of atomic
physics and relevant absorption edges, the lectures consider
electromagnetic radiation at short wavelengths, including
dipole radiation, scattering, and refractive index using a
semiclassical atomic model. Subject matter will include the
generation of x rays with synchrotron radiation, laser-plasma
sources, high harmonic generation, x-ray/EUV lasers, and black-body
radiation. Concepts of spatial and temporal coherence will
be described. Topics in x-ray optics will include total external
reflection, multilayer coatings, zone-plate (diffractive)
lenses, interferometry, microscopes, and EUV telescopes. Applications
will include high-resolution (20-nm) soft-x-ray microscopy
with applications to the life and physical sciences, with
elemental and chemical sensitivity. New results from three-dimensional
imaging of biological samples using high-resolution nanotomography
will be presented. EUV lithography for future 20-GHz nanoelectronic
devices with features smaller than 20 nm will also be discussed.
Contact: David Attwood, attwood@eecs.berkeley.edu
UEC Corner: Notes
from the Users'
Executive Committee
by Dennis Lindle
 As
incoming chair of the UEC, I would like to begin by expressing
a hearty thank you to past chair Jennifer Doudna for a job
well done in 2003—thanks Jennifer! The UEC also welcomes
three new members in 2004: Clemens Heske, Corie Ralston, and
Ed Westbrook. I look forward to working with them in the coming
year. Finally, I would like to acknowledge the contributions
of Gerry McDermott, especially as co-chair of the 2003 ALS
Users' Meeting, who just completed his term on the UEC—thanks
Gerry!
To begin, perhaps a brief introduction
of the new chair is in order. I have been a synchrotron-radiation
user since beginning my graduate studies in 1978, and I've
been addicted ever since. Over the years, I have gotten my
fix alternately at SSRL, NSLS, the SRC, and, of course, the
ALS. I am a Professor of Chemistry at the University of Nevada,
Las Vegas, and my primary research interests are in atomic
and molecular spectroscopy. My group is a regular user of
two-bunch mode, which we require for time-of-flight analysis
of photoelectron energies, as well as multibunch operation,
and we work on several different beamlines at the ALS. Also,
those of you who have been at the ALS for a while probably
remember this is my second term as chair of the UEC; I was
previously chair in 1991.
The UEC is looking forward to a busy
year. We expect to be involved with issues such as the proposed
ALS upgrades, planning the new user services building, and
what we usually refer to as "quality of life" issues
(housing, parking, etc.). As always, the UEC will take a leading
role in organizing the 2004 ALS Users' Meeting. Please remember
the UEC represents the entire user community at the ALS, and
every one of us on the committee is eager to hear from you
with any comments, concerns, or suggestions you might have
about the ALS. The current membership can be found on the
ALS web site. Please feel free to contact me or any of the
other members
of the UEC.
Contact: Dennis Lindle, lindle@unlv.nevada.edu
Compendium of
User Abstracts:
Tell us what you think
In the beginning, there was light. And
the people wanted to know what the light was used for, and
by whom. Thus, the ALS Compendium of User Abstracts was born.
Ever since the ALS opened in 1993, it has collected and published
a Compendium of the work performed here each year and distributed
it to users, funding agencies, and other interested parties.
Although the Compendium page is one of the most-visited pages
on our Web site, this product also consumes a finite amount
of (increasingly scarce) resources that might perhaps be put
to better use elsewhere.
The ALS would like to hear from users:
Do you use the Compendium? How valuable is it, in comparison
to other communication products such as the Activity Report,
ALSNews, beamline data sheets, science highlights, etc.? Would
a scaled-back version (e.g., just an online database) be worthwhile?
Perhaps it should be an ongoing, year-round activity instead
of an annual compilation? Please send any ideas, comments,
and suggestions you might have to Lori Tamura (LSTamura@lbl.gov).
Contact: Lori Tamura, LSTamura@lbl.gov
ALSNews undergoes
transformation
in 2004
Over the next few months, ALSNews will be undergoing
some changes. Starting with this issue, ALSNews will be distributed
once a month instead of biweekly. The Web version of the newsletter
is also being redesigned to allow the inclusion of more graphics
and to better reflect the design of the overall ALS site.
In the future, look for an emailed HTML newsletter that incorporates
graphics and links to more detailed information. As always,
your feedback is welcome.
Contact: Lori Tamura, LSTamura@lbl.gov
Nanoscience brochure
now
available online
The ALS recently published a brochure
featuring the opportunities for nanoscience research at the
ALS. A PDF
version of the brochure (499 K) is now available.
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