Inside Salk - May 2011 - page 10

Nuclear pore complexes, the
communication channels that regulate passage
of molecules to and from a cell’s nucleus, are
made up of proteins known as nucleoporins.
In studying nucleoporins,
Martin Hetzer
Hearst Endowment associate professor in
Salk’s Molecular and Cell Biology Lab,
discovered that the organization and archi-
tecture of the cell nucleus influences gene
activity, playing a role in the organization
of the genome and a very direct role in gene
expression. This finding is significant because
one of the hallmarks of cancer is abnormal
organization of the cell nucleus.
“Over the past 50 years, scientists were
limited to studyingmolecular mechanisms
either in the test tube or on fixed cells,”
he says, “but this hasmajor limitations.
TheWaitt Center core facility is vital to
our research because of its live cell
imaging capacity.”
Using conventional light microscopes,
nuclear pore complexes appear simply as
fuzzy dots of light. Even electronmicroscopes,
which have a superior resolution, cannot be
used to study these protein complexes in
living cells. Advancedmicroscopy in the
biophotonics core facility, however, has allowed
Hetzer to visualize the nuclear pore complexes
at the structural level as they are assembled
and inserted into the nuclear membrane.
Looking ahead, super-resolutionmicroscopy
will allow him to drill still deeper into the
individual components of nuclear pore
complexes in living cells.
“Our goal is to visualize transcription
and expression of a gene inside a nucleus in
real time as tissue undergoes developmental
processes,” he says. “What makes this so
exciting for us is that nucleoporins are key
regulators for developmental genes and also
potential markers for causes of cancer.”
: Training a spotlight on the nucleus
TheWaitt Center core
facility is vital to our
research because of its
live cell imaging capacity.
Martin Hetzer
Dannielle Engle, a graduate student, works in the laboratory of GeoffWahl, professor in theGeneExpression Laboratory.
Lead Story
Inside Salk 05 |11
1,2,3,4,5,6,7,8,9 11,12,13,14,15,16,17,18,19,20,...32
Powered by FlippingBook