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TRPV3 is a calcium-permeable temperature-sensitive cation channel 总被引:37,自引:0,他引:37
Xu H Ramsey IS Kotecha SA Moran MM Chong JA Lawson D Ge P Lilly J Silos-Santiago I Xie Y DiStefano PS Curtis R Clapham DE 《Nature》2002,418(6894):181-186
Transient receptor potential (TRP) proteins are cation-selective channels that function in processes as diverse as sensation and vasoregulation. Mammalian TRP channels that are gated by heat and capsaicin (>43 degrees C; TRPV1 (ref. 1)), noxious heat (>52 degrees C; TRPV2 (ref. 2)), and cooling (< 22 degrees C; TRPM8 (refs 3, 4)) have been cloned; however, little is known about the molecular determinants of temperature sensing in the range between approximately 22 degrees C and 40 degrees C. Here we have identified a member of the vanilloid channel family, human TRPV3 (hTRPV3) that is expressed in skin, tongue, dorsal root ganglion, trigeminal ganglion, spinal cord and brain. Increasing temperature from 22 degrees C to 40 degrees C in mammalian cells transfected with hTRPV3 elevated intracellular calcium by activating a nonselective cationic conductance. As in published recordings from sensory neurons, the current was steeply dependent on temperature, sensitized with repeated heating, and displayed a marked hysteresis on heating and cooling. On the basis of these properties, we propose that hTRPV3 is thermosensitive in the physiological range of temperatures between TRPM8 and TRPV1. 相似文献
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Voltage changes across the cell membrane control the gating of many cation-selective ion channels. Conserved from bacteria to humans, the voltage-gated-ligand superfamily of ion channels are encoded as polypeptide chains of six transmembrane-spanning segments (S1-S6). S1-S4 functions as a self-contained voltage-sensing domain (VSD), in essence a positively charged lever that moves in response to voltage changes. The VSD 'ligand' transmits force via a linker to the S5-S6 pore domain 'receptor', thereby opening or closing the channel. The ascidian VSD protein Ci-VSP gates a phosphatase activity rather than a channel pore, indicating that VSDs function independently of ion channels. Here we describe a mammalian VSD protein (H(V)1) that lacks a discernible pore domain but is sufficient for expression of a voltage-sensitive proton-selective ion channel activity. H(v)1 currents are activated at depolarizing voltages, sensitive to the transmembrane pH gradient, H+-selective, and Zn2+-sensitive. Mutagenesis of H(v)1 identified three arginine residues in S4 that regulate channel gating and two histidine residues that are required for extracellular inhibition of H(v)1 by Zn2+. H(v)1 is expressed in immune tissues and manifests the characteristic properties of native proton conductances (G(vH+)). In phagocytic leukocytes, G(vH+) are required to support the oxidative burst that underlies microbial killing by the innate immune system. The data presented here identify H(v)1 as a long-sought voltage-gated H+ channel and establish H(v)1 as the founding member of a family of mammalian VSD proteins. 相似文献
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The question of the coexistence and potential interaction between the last Neanderthal and the earliest intrusive populations of anatomically modern humans in Europe has recently emerged as a topic of lively debate in the archaeological and anthropological literature. Here we report the results of radiocarbon accelerator dating for what has been reported as an interstratified sequence of late Neanderthal and early anatomically modern occupations at the French type-site of the Chatelperronian, the Grotte des Fées de Chatelperron, in east-central France. The radiocarbon measurements seem to provide the earliest secure dates for the presence of Aurignacian technology--and from this, we infer the presence of anatomically modern human populations--in France. 相似文献
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Scytonotus granulatus (Say, 1821) (Polydesmida: Polydesmidae), the most widely ranging polydesmid species in North America and the 4th most widely distributed indigenous continental milliped, is recorded from LeFlore and Latimer Counties, Oklahoma, and Jackson County, Alabama, the 1st records from these states. It also occurs in Logan and Independence Counties, Arkansas. The Latimer County record corresponds approximately to the terminus of the eastern forested biome and extends the distributions of the species and the genus some 255 miles (408 km) westward; along with literature records from Shawnee County, Kansas, and Cass County, Nebraska, it constitutes the western range limits. The projected overall distribution extends around 1100 miles (1760 km) east-west and 985 miles (1576 km) north-south and encompasses parts of Ontario, Québec, and 19 states, including all of Pennsylvania, West Virginia, Ohio, Indiana, and Illinois. New localities are detailed as are those from Missouri and that from Dare County, on the Outer Banks of North Carolina. 相似文献
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Virgoiulus minutus (Brandt 1841) (Julida: Blaniulidae), the only indigenous representative of the family in the New World, occurs, or can be expected, in parts or all of 24 states east of the Central Plains plus the District of Columbia; it is documented for the 1st time from Mississippi, Oklahoma, and Texas. The northern-, southern-, and westernmost localities are in Berrien County, Michigan; Putnam County, Florida; and Angelina/Rusk Counties, Texas, respectively. New England, Utah, Wyoming, Canada, and Mexico are deleted from the range, and specific localities are reported to augment previous generalized citations; those from Mexico represent misidentifications of Nopoiulus kochii (Gervais, 1847), an introduced European species that is recorded from Mexico City, Distrito Federal. Records of V. minutus from Pennsylvania, Virginia, South Carolina, Georgia, Alabama, West Virginia, Ohio, Illinois, Michigan, and Missouri are the 1st definite localities from these states; a sample from ""Anechar,"" believed to be a misspelling of ""Arrochar,"" a neighborhood in Staten Island, is considered the 1st definite record from New York. The published statement of occurrence in Delaware in general is the only known record of an indigenous diplopod from this state. 相似文献
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Locations of 73,219 vascular plant vouchers representing 2438 species were digitized from the Atlas of the Vascular Plants of Utah (Albee et al. 1988). Source maps consist of 1:6,000,000-scale shaded relief maps of Utah with points representing collection locations by species. Location points, representing 1 or more specimens, were transposed onto these maps from the approximately 400,000 herbarium records of 3 major universities and federal land management agencies. These source maps were digitized into an ARC/Info TM database in order to reproduce the atlas in digital form. Analysis of all locations revealed a mapping bias of the original authors to avoid placing sample locations on county boundaries and over major river corridors. A comparison between ecoregions and elevation showed that the Colorado Plateau and Wasatch/Uinta Mountains have the highest species diversity, and that areas of low elevation (1000-2000 m) have the highest number of unique species in the state. Further, species richness is related to elevation and to ecoregion boundaries. 相似文献