- RACHEL FINK
- Associate Professor of
- South Hadley, Ma 01075
- email: email@example.com
- My research has focused on questions
of embryonic cell rearrangements. As an embryo develops from
a fertilized egg, cells are constantly dividing, migrating, differentiating
and rearranging. Time-lapse video microscopy reveals these movements
and allows analysis of the cellular mechanisms driving these
transformations. My embryo of choice is that of the killifish,
Fundulus heteroclitus, and I have been focusing
on the rearrangements of a group of epithelial cells that form
the first embryonic skin. These embryos are large and transparent,
and are ideal for microscopy. To make the invisible visible individual
embryonic cells are labeled with fluorescent lipids. Fluorescence
and confocal microscopy can be used to watch an individual epithelial
cell in vivo, as the entire sheet of cells rearranges
and spreads to cover the large yolk sac. These films document
that individual cells are extremely dynamic, sending and retracting
long protrusions that underlap neighboring cells.
This system can also be used to study membrane turnover in epithelial
cells. All cells are constantly adding new material to their
membranes, and internalizing regions of surface membrane. This
turnover has tremendous ramifications for most cell behaviors.
The Fundulus embyronic epithelial cells are remarkable
in that many of these fluorescent lipids are immobile in the
plane of the membrane, allowing long-term (1-5 days) observation
of membrane turnover. This turnover is accelerated near sites
of cell-cell contact. The most exciting part of this work is
that membrane turnover is accelerated when the cells are under
mechanical tension. That is, cells actively rearranging turn
over their marginal domains faster than cells that are not under
I am also involved in making research video footage available
for teaching, and have published two compilations of movies.
A Dozen Eggs: Time-Lapse Microscopy of Normal Development
was published by Sinauer Associates under the auspices of
the Society for Developmental Biology. CELLebration was
published by Sinauer Associates and the American Society for
Cell Biology. Currently I am compiling sequences filmed by my
undergraduate students for use in a web-based project to introduce
younger audiences to the wonderful world of cells and embryos.
At any time in my lab students might be filming fern sperm release,
cell movements in hydra, sea urchin gastrulation and/or keratocyte
- Click on the images above
for more information.
1. Fink, R.D. and Cooper, M.S. (1996)
Apical membrane turnover is accelerated near cell-cell contacts
in an embryonic epithelium. Devel. Biol. 174, 180-189.
2. Fink, R.D. (Ed.) (1995) CELLebration. American Society
for Cell Biology and Sinauer Associates, Inc. Video, 37 min.
3. Fink, R.D. (Ed.) (1991) A Dozen Eggs: Time-Lapse Microscopy
of Normal Development. Society for Developmental Biology and
Sinauer Associates, Inc. Video, 43 min.