| Kuriyan
Lab Describes DNA Sliding Clamps in Nature
John Kuriyan and his team have solved the protein structure
of an important complex involved in DNA replication.
Their findings, which appear in this month’s Nature,
help illustrate the mechanism by which DNA polymerase
– the protein responsible for DNA duplication
– attaches to DNA to begin its work. DNA polymerase
must begin replication right where double-stranded DNA
becomes a single strand. This involves the DNA sliding
clamp, a ring-shaped protein that helps DNA polymerase
hold on to and slide down a single strand of DNA. The
Kuriyan Lab determined the exact structure of this ring-shaped
clamp protein and a larger five-protein complex known
as the clamp loader, which helps direct DNA polymerase
to exactly the right spot, thus enabling rapid replication.
Read the Nature
article here
Tugging on Condensin
Unravels Protein’s Mysteries
By delicately stretching a protein to its limits, Carlos
Bustamante and a team of researchers have begun to show
how the ubiquitous condensin molecule helps coil an
entire meter of DNA into each human cell. Discovered
just ten years ago, condensins are found in all organisms,
from bacteria to humans. Bustamante and the team were
able to stretch condensin-compacted DNA molecules between
two beads, observing the results as the bonds between
the condensin molecules snapped. From the details, published
in the June edition of Science, the team could infer
how condensin molecules are assembled within the DNA
fiber. This mechanistic approach to characterizing proteins
complements methods such as crystallography, genetics
and biochemistry, and these particular results promise
insight into a family of proteins with such crucial
functions as DNA repair and meiosis. Read
the Science article here
Oxygen-Sensing
in Worms May Hold Key to Healthy Blood Pressure in Humans
What began as a simple study of how a human enzyme binds
nitric oxide blossomed into a collaborative effort resulting
in a richer understanding of how organisms sense and
use oxygen. Guanlyate cyclase is a human enzyme that
detects nitric oxide, which is important in relaxing
and dilating blood vessels, and has roles in central
nervous system and immune function. Michael Marletta
was studying the human enzyme when he came across GCY-35,
an almost genetically identical enzyme in the nematode
Caenorhabditis elegans. Now, Marletta and a group of
researchers from across the nation have pieced together
how the nematode actually uses GCY-35 to sense oxygen
in its environment. The group believes this helps the
nematode find areas of low oxygen concentration, where
its oxygen-devouring bacterial food is most likely to
be found. Because of the similarities between human
and nematode enzymes, the findings may have significance
in human health, such as healthy blood pressure. The
research team’s findings are reported in the
July 15 edition issue of Nature, as well
as Berkeley
Lab’s Research News.
Liphardt Discusses Biobot
Progress in Berkeley Lab View
With potential applications in medicine, national security
and environmental protection, biobots may mark the transformation
of biology from a largely descriptive discipline to
one where, in the words of Jan Liphardt, “we can
use what we know about biological systems to build new
things.” In this month’s Berkeley Lab View,
Liphardt discusses the latest developments in his area,
including pioneering experiments extending theoretical
thermodynamics into the tiny world of living things
to quantify biomolecular systems in ways previously
thought impossible. Read
the Berkeley Lab View article
Giving Credit Where
Credit Is Due: DOE Citations
All Laboratory scientific and technical publications
funded entirely or in part by the DOE must carry a standard
credit line on the title page showing the funding source,
the DOE/Laboratory contract number, and any applicable
Laboratory non-DOE contract number. Click
here for a simple guide to doing it right
McDermott Receives DOE
Outstanding Mentor Award
Gerry McDermott, Operations Head of the Berkeley Center
for Structural Biology (BCSB), has been recognized as
a 2003 Outstanding Mentor for the Department of Energy.
McDermott was one of four LBNL mentors selected for
the award based on how long they have been mentoring,
their contribution to DOE and Lab educational goals,
and their contribution to encouraging student professional
and academic success. McDermott was presented with the
award, signed by the Secretary of Energy, at a special
event on June 25.
Mark Your Calendars: PBD
Summer Picnic
The Physical Biosciences Summer Picnic is on Friday,
September 24 at noon at the Padre Site in Tilden Park.
Food, friends and fun will abound! See
pictures of last year's picnic
Student Seminar and Pizza
Social
PBD Students are invited to a first-of-its-kind Pizza
Social on Monday, August 2 at 4 pm in the Calvin Seminar
Room. Jamie Cate will be talking about ongoing research
in his lab, after which there will be a tour of the
Cate Lab and pizza and drinks. Visit
our Student Page for more information and resources
available to students in our division.
|
