Crickets offer an excellent model to test the interference of genetic programs with environmental cues during the development and regeneration of neuronal networks.
Cricket gravity sense organs and related responses are well defined.
The experiment CRISP flew on NASA's NEUROLAB-Mission (STS-90) April-May 1998.
We sent eggs and young crickets to space via Space Shuttle Columbia. The animals developed in microgravity, a control group was kept under same conditions on earth .
After the mission we tested morphological and physiological changes of the gravity sense organs.
Experiments included staining and electrophysiology of sensory neurons, position sensitive interneurons and behavioral studies (compensatory head movements).
More about this projects with results, pictures etc. will be posted after having overviewed the huge amount of data collected post-flight.
How do crickets detect gravity ???:
The gravity sensory system of the cricket is a composed field of sensory club-shaped hairs located with wind/sound sensitive hairs on the proximal part of the cerci (if you don't know where the cerci are
press here!). The number of these gravity sensitive hairs increases from one on each of the two body appendages in the first larval instar to about 150 in the adult animal.Underneath each of those club-shaped hairs there is one sensory neuron sending its axon to the terminal abdominal Ganglion (TAG) where the axon is making synaptic connections to a position sensitive interneuron (PSI). This interneuron is sending the processed information to the brain.
To observe changes that are only induced by the lack of gravity, another system, the wind-sensitive system (neighbouring the gravity system in the TAG) can be used as control.
Picture Gallery
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Shuttle - Pictures
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SEM - Pictures Part 1
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SEM - Pictures Part 2
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A Space-Grown PSI
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Microscope - Pictures
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The Astronauts in my Lab
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Some explanations to the pictures above:
Shuttle Pictures:
The Orbiter Columbia being rolled out from the Vehicle Assemly Building. No Animals aboard yet. The small picture shows Columbia's return after a 16-day mission. The astronauts bring back our crickets and the animals from the other 25 experimental teams (fish, snails, rats and mice)
SEM-Pictures :
On these Scanning Electron Microscope pictures you can see, where the club-shaped hairs are located (i.e. only one in the first larval instar -arrow-) and how they look like. They are organized in rows and their number increases when the cricket molts.
Microscope Pictures:
Pictures from the TAG, a Nerve-Cell agglomeration in the animals rear where the first information processing takes place. On the left side is a MGI, an Interneuron responding to wind stimuli, in the middle a PSI, on the right side a sensory axon branching.
All pictures copyright P.Riewe (1998) except "Astronauts in my Lab" by NASA
For more info about the project or current results: Mail me!
To see the department where I am preparing my Ph.D. Thesis (Dept. of Comp. Neurobiology: Click here!
To visit the NEUROLAB/CRISP page in this department (incl. a nice video of the shuttle landing): Click here
To see the official Neurolab brochure including all 26 experiments aboard Columbia (we are the Neurobiology Team): click here
To meet the project leader (PI = Principal Investigator): Click here
To proceed to the official Neurolab Homepage : Click here
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Crickets in Space 
