只有四種哺乳動(dòng)物已知擁有能夠探測(cè)紅外線的“第六感”，它既被用于捕食目的,，也被用于熱調(diào)控目的。
這些動(dòng)物包括三種有遠(yuǎn)親關(guān)系的蛇（頰窩毒蛇和兩種蟒蛇：英文名稱分別為python和boa）及吸血蝙蝠,。調(diào)控這一感覺(jué)的頰窩器官?gòu)慕馄式嵌群托袨榻嵌榷际艿搅藦V泛研究,，但對(duì)紅外線探測(cè)能力背后的信號(hào)傳導(dǎo)機(jī)制或所涉及的分子人們卻知之甚少,。
現(xiàn)在，Gracheva等人發(fā)現(xiàn),，有頰窩的蛇依賴離子通道TRPA1來(lái)精確探測(cè)熱量,。這一發(fā)現(xiàn)增加了TRPA1家族蛋白所具有的探測(cè)功能，這些蛋白在哺乳動(dòng)物中探測(cè)刺激性化學(xué)物質(zhì),、在昆蟲中探測(cè)熱變化,。(生物谷Bioon.com)
生物谷推薦原文出處：
Nature doi:10.1038/nature08943
Molecular basis of infrared detection by snakes
Elena O. Gracheva1,6, Nicholas T. Ingolia2,3,4,6, Yvonne M. Kelly1, Julio F. Cordero-Morales1, Gunther Hollopeter1,7, Alexander T. Chesler1, Elda E. Sánchez5, John C. Perez5, Jonathan S. Weissman2,3,4 & David Julius1,2
Department of Physiology,
Department of Cellular and Molecular Pharmacology,
Howard Hughes Medical Institute,
California Institute for Quantitative Biosciences, University of California, San Francisco, California 94158-2517, USA
Natural Toxins Research Center, Texas A&M University- Kingsville, Texas 78363, USA
These authors contributed equally to this work.
Present address: Department of Biology, University of Utah, 257 South 1400 East, Salt Lake City, Utah 84112-0840, USA.
Snakes possess a unique sensory system for detecting infrared radiation, enabling them to generate a ‘thermal image’ of predators or prey. Infrared signals are initially received by the pit organ, a highly specialized facial structure that is innervated by nerve fibres of the somatosensory system. How this organ detects and transduces infrared signals into nerve impulses is not known. Here we use an unbiased transcriptional profiling approach to identify TRPA1 channels as infrared receptors on sensory nerve fibres that innervate the pit organ. TRPA1 orthologues from pit-bearing snakes (vipers, pythons and boas) are the most heat-sensitive vertebrate ion channels thus far identified, consistent with their role as primary transducers of infrared stimuli. Thus, snakes detect infrared signals through a mechanism involving radiant heating of the pit organ, rather than photochemical transduction. These findings illustrate the broad evolutionary tuning of transient receptor potential (TRP) channels as thermosensors in the vertebrate nervous system.
