TY - JOUR
T1 - A sensory neuron-specific, proton-gated ion channel
AU - Chen, Chih Cheng
AU - England, Steven
AU - Akopian, Armen N.
AU - Wood, John N.
PY - 1998/8/18
Y1 - 1998/8/18
N2 - Proton-gated channels expressed by sensory neurons are of particular interest because low pH causes pain. Two proton-gated channels, acid-sensing ionic channel (AS/C) and dorsal root ASIC (DRASIC), that are members of the amiloride-sensitive ENaC/Degenerin family are known to be expressed by sensory neurons. Here, we describe the cloning and characterization of an ASIC splice variant, ASIC-β, which contains a unique N-terminal 172 aa, as well as unique 5' and 3' untranslated sequences. ASIC-β, unlike ASIC and DRASIC, is found only in a subset of small and large diameter sensory neurons and is absent from sympathetic neurons or the central nervous system. The patterns of expression of ASIC and ASIC-β transcripts in rat dorsal root ganglion neurons are distinct. When expressed in COS-7 cells, ASIC-β forms a functional channel with electrophysiological properties distinct from ASIC and DRASIC. The pH dependency and sensitivity to amiloride of ASIC-β is similar to that described for ASIC, but unlike ASIC, the channel is not permeable to calcium, nor are ASIC-β-mediated currents inhibited by extracellular calcium. The unique distribution of ASIC-β suggests that it may play a specialized role in sensory neuron function.
AB - Proton-gated channels expressed by sensory neurons are of particular interest because low pH causes pain. Two proton-gated channels, acid-sensing ionic channel (AS/C) and dorsal root ASIC (DRASIC), that are members of the amiloride-sensitive ENaC/Degenerin family are known to be expressed by sensory neurons. Here, we describe the cloning and characterization of an ASIC splice variant, ASIC-β, which contains a unique N-terminal 172 aa, as well as unique 5' and 3' untranslated sequences. ASIC-β, unlike ASIC and DRASIC, is found only in a subset of small and large diameter sensory neurons and is absent from sympathetic neurons or the central nervous system. The patterns of expression of ASIC and ASIC-β transcripts in rat dorsal root ganglion neurons are distinct. When expressed in COS-7 cells, ASIC-β forms a functional channel with electrophysiological properties distinct from ASIC and DRASIC. The pH dependency and sensitivity to amiloride of ASIC-β is similar to that described for ASIC, but unlike ASIC, the channel is not permeable to calcium, nor are ASIC-β-mediated currents inhibited by extracellular calcium. The unique distribution of ASIC-β suggests that it may play a specialized role in sensory neuron function.
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U2 - 10.1073/pnas.95.17.10240
DO - 10.1073/pnas.95.17.10240
M3 - Article
C2 - 9707631
AN - SCOPUS:0032544025
SN - 0027-8424
VL - 95
SP - 10240
EP - 10245
JO - Proceedings of the National Academy of Sciences of the United States of America
JF - Proceedings of the National Academy of Sciences of the United States of America
IS - 17
ER -