Second cold-sensing protein found. (Biology).They're on a hot streak. Researchers who last year discovered a mammalian cell-surface protein that senses coolness--and the presence of menthol--have now found a protein that enables nerve cells to recognize much colder temperatures (SN: 2/16/02, p. 101). Whereas the cool-menthol receptor kicks in around 25[degrees]C, the newly identified receptor doesn't trigger nerve cells until the thermometer thermometer, instrument for measuring temperature. Galileo and Sanctorius devised thermometers consisting essentially of a bulb with a tubular projection, the open end of which was immersed in a liquid. falls below 15[degrees]C, Ardem Patapoutian of the Scripps Research Institute in La Jolla La Jolla (lə hoi`yə), on the Pacific Ocean, S Calif., an uninc. district within the confines of San Diego; founded 1869. The beautiful ocean beaches, in particular La Jolla shores and Black's Beach, and sea-washed caves attract visitors and , Calif., and his colleagues report in the March 21 Cell. They had suspected that an additional temperature sensor exists because other scientists had recently documented nerve cells that respond to cold temperatures but not to menthol menthol, white crystalline substance with a characteristic pungent odor. It is derived from the oil of the peppermint plant, Mentha piperita (see mint), or prepared synthetically from coal tar. . The two cold-activated receptors are related in structure, but their amino acid amino acid (əmē`nō), any one of a class of simple organic compounds containing carbon, hydrogen, oxygen, nitrogen, and in certain cases sulfur. These compounds are the building blocks of proteins. makeup is very different, the researchers report. Curiously, the new cold receptor is found on nerve cells that also sport a receptor for hot temperatures and capsaicin capsaicin /cap·sa·i·cin/ (kap-sa´i-sin) an alkaloid irritating to the skin and mucous membranes, the active ingredient of capsicum; used as a topical counterirritant and analgesic. cap·sa·i·cin n. , the chemical that gives chilies and other foods their fiery kick. |
|
||||||||||||||||||||
Printer friendly
Cite/link
Email
Feedback
Reader Opinion