The nematode Caenorhabditis elegans can "remember" the temperature at which it was grown and will seek out that temperature if later exposed to a gradient of temperatures. In an effort to define the neuronal circuitry that allows this behavior, Kuhara et al. found that a neuron known as AWC has an important role in sensing temperature. This came as a surprise because the AWC cell is also known to function as an olfactory neuron. The cell could respond independently to odorants and temperature, even though when sensing temperature the neuron used a G protein-mediated intracellular signaling system similar to that used in olfactory responses.
A. Kuhara, M. Okumura, T. Kimata, Y. Tanizawa, R. Takano, K. D. Kimura, H. Inada, K. Matsumoto, I. Mori, Temperature sensing by an olfactory neuron in a circuit controlling behavior of C. elegans. Science 320, 803-807 (2008). [Abstract] [Full Text]