Adapting to an extreme life
It’s not an exaggeration to say that nematodes are everywhere; they make themselves at home in ocean trenches, polar ice caps, a mile underground, and within our own intestines. So, when Lee joined the group of researchers going to survey Mono Lake’s harsh environment for nematodes, he said, “We knew that there were going to be worms there. And we knew two things. One, this would be great for extremophile biology…and number two, that we could get a great field trip out of this.”
He laughed. “It had a lot to do with the latter.”
The team was right — they found not one, but eight species of nematodes in Mono Lake. Tokorhabditis tufae, which was a new species at the time, stood out in particular for its high arsenic resistance and the unusual nematode behavior of live birth. The latter adaptation is especially fascinating. As each egg hatches within the mother, the young seem to “stack inside there like sardines,” Lee said, “and the mother seems fine with it.”
Lee was fascinated by this worm. Fortunately, T. tufae grows and reproduces under the same conditions as the well-studied nematode C. elegans, so it can easily be cultured in the lab.
Lee thinks that a key to T. tufae’s extreme tolerance might lie in its “birthing circuit,” the cluster of neurons that govern its birthing behavior. In C. elegans, this circuit is well-studied: Every neuron is named, the neurotransmitters that trigger it have been identified, and the timing of birth is precisely known. What Lee wants to do is recreate this knowledge for T. tufae. To do so, he is using many of the same methods those first C. elegans researchers used.
“I'm going back to old school techniques,” Lee said.