- By:
Stu Hutson – (352) 273-3569 - Sources:
Peter Hansen – pjhansen@ufl.edu, (352) 392-5590
Neil Talbot – neil.talbot@ars.usda.gov, (301) 504-5123
GAINESVILLE, Fla. — Mankind’s quick trips to space haven’t had to cope with many problems that come with a longer stay off-planet, but research aboard the next shuttle mission will address one issue bound to come up in the foray to the final frontier – extraterrestrial motherhood.
The experiment will observe the progress of just-fertilized cow embryos as they divide and develop in the microgravity environment of the space shuttle. The experiment, which is expected to go up on the November 14 launch of the shuttle Endeavour, will be the first to examine how early-stage mammalian life develops under these conditions.
“There’s a lot of uncertainty about how embryos at this stage do what they do – it’s true in cows, and ob-gyns will tell you the same thing about human embryos,” said Peter Hansen, an animal sciences professor at the University of Florida’s Institute of Food and Agricultural Sciences. “It’s anyone’s guess what they’ll do in space.”
Hansen’s team is working with NASA, the U.S. Department of Agriculture’s Agricultural Research Service and Zero Gravity Inc., a Maryland-based company. Hansen will provide the embryos and will help analyze them upon their return to Earth 15 days later.
Several hundred cow eggs will be fertilized in test tubes just a day or two before the shuttle launch. During the flight, they should grow into tiny embryos composed of about 100 cells that are organized into only three types of primitive tissue. These embryos will be fixed with a preservative on the eighth and on the final day of the shuttle flight for analysis back on Earth.
Along with giving the researchers a first glimpse of how mammalian embryos tough out space travel, the work may also offer some clues about how a perfectly spherical ball of cells begins to grow into a body’s irregular shape.
A variety of biological mechanisms may play a part in directing embryo growth. For example, chemicals that spur the growth of specific types of cells disperse at different parts of the early embryo.
However, a lack of gravity may interfere with this dispersion. Alternatively, the cells, unencumbered by the stressing forces of gravity, may actually grow at faster rates.
The researchers will also observe how pig liver stem cells grow, function and self-organize in microgravity – a portion of the experiment that the researchers affectionately refer to as “pigs in space.”
“There are a lot of changes in human and animal physiology that we know occur during space travel,” said Neil Talbot, a USDA-ARS agricultural researcher and principal investigator on the work. “Fluids are redistributed, bone density changes and so on. But how a lack of gravity affects cell growth and normal cell-to-cell self-organization is another question. You might expect some unique phenomenon at the cellular level, and this will be the focus of the experiment.”
Of course, not all of the cells will survive the trip, but even those are of benefit to science. Hansen’s group is eager to examine the embryos to learn more about how the stress of space flight might affect the natural process of cell death.
“Even healthy embryos terminate some of their cells as they grow,” Hansen said. “This is just another chance to examine how that process works under a very unusual set of circumstances.”
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