SURJ
Spotlight on Emily Abrash: Developmental
Plant Biology Research affects Global
Warming
Karis Tang-Quan1
While engineers are creating
fuel cells with lower gas emissions
and politicians debate the best way to
limit air pollution, one young biologist
is studying the systems that control
stomatal production and distribution in
plants to counter the effects of global
warming. Most people do not think
plant biology can have a great effect on
environmental issues such as the rising
carbon dioxide levels in the earth’s
atmosphere, but Emily Abrash believes
her research can make a difference.
As a college freshman at
Carleton College, Emily thought she
was going to be a successful History
or Classics major. She has the ability
to communicate her ideas articulately
and enjoys writing. However, one
plant development class changed the
direction of her college career. Emily
was intrigued with the biology subjects
and wanted to know more about
the research process. When Emily
transferred to Stanford as a sophomore,
she actively searched for a biology
laboratory. Her biology research career
began in Dr. Dominique Bergmann’s
lab in the Department of Biological
Sciences.
Dr. Bergmann, an assistant
professor of Biology, leads a
research group that uses Arabidopsis
stomatal development as a model for
understanding tissue patterning and
cell fate. The lab is unique in its study
of both the genetic and environmental
factors on the binary cell fate
decision. This Stanford lab focuses
its attention on the molecular genetics
underlying production, patterning,
and morphogenesis of stomata and the
1Stanford University
epidermal cellular valves that regulate
plant gas exchange. Due to its control
over the plant’s rate of photosynthesis
and respiration, the stoma is a crucial
part of the plant for scientists to
understand. Stomatal development
can influence global warming as well
as give researchers more information
on environmental fluctuations and
biofuels.
Emily began her research by
studying a mutation in Arabidopsis
thaliana
that
was
previously
discovered by Dr. Bergmann who was
a post-doctoral fellow at the time. The
characterization of the CHALLAH
family of proteins is important as they
it appears to play a tissue-specific role
in stomatal patterning. For the first
year, Emily mapped the CHALLAH
mutation, narrowing it down to a
specific chromosomal region. With a
candidate gene approach, Emily cloned
and identified the gene. She found that
the nature of the protein product was a
small, potentially ligand-like molecule.
This identification and characterization
of the CHALLAH gene was just the
beginning of Emily’s research.
After isolating and cloning
the CHALLAH gene mutation, Emily
realized it had two putative homologues
in the entire genome. She was then able
to examine the phenotypes of double
and triple CHALLAH family mutants.
By knocking out the two homologues
in experimentation, Emily is studying
how the proteins interact with a
particular family of plasma membrane
receptors. These receptors are known
to play a role in stomatal development
of the plant. Emily looks for phenotype
similarities between her knockout and
crosses of knockout lines. Additional
over-expression samples and GUS
(β-glucuronidase)
transcriptional
reporters are used in experimentation
to study the CHALLAH gene.
As
mentioned
before,
Emily’s research has a place in the
greater picture of global warming.
Though it is specific to the stomatal
development and patterning in plants,
her research provides insight to
controlling a plant’s ability to fix carbon
dioxide and to prevent water loss. The
molecular mechanisms that a plant
carries out are important to the state
of the environment. By understanding
the systems of stomatal production and
distribution, environmentalists will
have a better approach to the tough
issues such as global warming.
Figure 1: Large clusters of stomata on the
hypocotyl (seedling stem) of a CHALLAH
family triple mutant in a too many mouths
background.
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Special Features
Just as Emily believed
she would pursue her interest in
history or the Classics but changed
her area of study, so as her research
been a constantly evolving process.
Emily began by simply trying to
identify CHALLAH, yet she has
made a significant contribution to
understanding the interactions between
plants and the environment. Emily
attributes her wonderful lab experience
to her great mentor Dr. Bergmann and
supportive labmates.
Emily continues to use her
communication skills as she pursues
her scientific interests. At the American
Society of Plant Biologists 2007
Summer Conference, Emily presented
her research poster. Supported by the
American Society of Plant Biologists
SURF program, the Biological Sciences
VPUE program, and a URP major
grant, she hopes to publish her findings
in a specialized developmental journal.
Figure 2: Leaf epidermis of a plant overexpressing CHALLAH. The arrows indicate stomatal
lineage cells that have failed to differentiate as stomata.
Emily Abrash transferred to Stanford in the fall of 2005 as a sophomore. She will graduate this
spring with a Biological Sciences major. After spending a year teaching abroad in Latin America,
Emily plans to pursue a Ph.D. in developmental biology. At Stanford, Emily is actively involved
with Science Bus, a group of undergraduate and graduate students who volunteer their time to run an
after-school science program in East Palo Alto.
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