How to study cells,
one by one
By Susan Gaidos
Fly over any baseball stadium when the home-team batter slams a double in the gap with twomen onbase, andyou’llseea
crowd of fans rising in unison, arms waving wildly in the air. You’d think you were
viewing typical baseball fan behavior.
Witness this scene at ground level,
though, and you’ll get a different picture. While a majority of fans participate
in the cheering, others are sipping beer,
attending to scorecards or roaming the
walkways in search of a hot dog.
Such displays of individuality
shouldn’t come as a surprise — people
often react differently to the same circumstances, after all. But life’s individuality thrives at much smaller scales than
the human body.
Cells, for example, are not all alike.
Clusters of single cells, even of all the
same type, show cell-to-cell differences
in appearance, growth and behavior.
This holds true for single-celled organisms too. Individuals within a colony
of identical bacteria, for instance, will
behave in different ways, even under the
same conditions.
For decades, scientists were stuck with
an aerial view of cell behavior. Experiments carried out on large pools of cells
obscured information on the activities
and makeup of the individuals. Difficulties in tracking molecules inside a single
cell forced researchers to content themselves with averages derived from whole
populations.
Despite being kept in the same lab con-
ditions, these human colon cells make
differing amounts of the protein beta-
catenin (green)in their nuclei (blue).
in. Improvements in imaging techniques
make it possible to view tiny, transparent structures and molecules within
cells that are otherwise nearly invisible.
New ways of separating cells during
study enable scientists to sort through
thousands at once, distinguishing subpopulations and studying multiple traits
in just one go.
“We used to think that we could take
a million cells and grind them up and
make measurements on those million
cells,” says Nancy Allbritton, a biomedical engineer at the University of North
CURTIS THORNE AND CHONLARAT (“PEARL”) WICHAIDIT
www.sciencenews.org
