Expression pattern in brain of TASK-1, TASK-3, and a tandem pore domain K(+) channel subunit, TASK-5, associated with the central auditory nervous system.
TWIK-related acid-sensitive K(+) (TASK) channels contribute to setting the resting potential of mammalian neurons and have recently been defined as molecular targets for extracellular protons and volatile anesthetics. We have isolated a novel member of this subfamily, hTASK-5, from a human genomic library and mapped it to chromosomal region 20q12-20q13. hTASK-5 did not functionally express in Xenopus oocytes, whereas chimeric TASK-5/TASK-3 constructs containing the region between M1 and M3 of TASK-3 produced K(+) selective currents. To better correlate TASK subunits with native K(+) currents in neurons the precise cellular distribution of all TASK family members was elucidated in rat brain. A comprehensive in situ hybridization analysis revealed that both TASK-1 and TASK-3 transcripts are most strongly expressed in many neurons likely to be cholinergic, serotonergic, or noradrenergic. In contrast, TASK-5 expression is found in olfactory bulb mitral cells and Purkinje cells, but predominantly associated with the central auditory pathway. Thus, TASK-5 K(+) channels, possibly in conjunction with auxiliary proteins, may play a role in the transmission of temporal information in the auditory system.
Karschin
C
C
Department of Molecular Neurobiology of Signal Transduction, Max-Planck-Institute for Biophysical Chemistry, Göttingen, Germany.
Wischmeyer
E
E
Preisig-Müller
R
R
Rajan
S
S
Derst
C
C
Grzeschik
K H
KH
Daut
J
J
Karschin
A
A
D000595:Amino Acid Sequence / Q000235:genetics; D000818:Animals; D001306:Auditory Pathways / Q000166:cytology / Q000378:metabolism*; D001483:Base Sequence / Q000235:genetics; D001921:Brain / Q000166:cytology / Q000378:metabolism*; D002874:Chromosome Mapping; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000235:genetics; D005260:Female; D005786:Gene Expression Regulation / Q000502:physiology*; D006801:Humans; D017403:In Situ Hybridization; D008564:Membrane Potentials / Q000235:genetics; D008969:Molecular Sequence Data; D009419:Nerve Tissue Proteins; D009474:Neurons / Q000166:cytology / Q000378:metabolism*; D009865:Oocytes / Q000166:cytology / Q000378:metabolism; D015221:Potassium Channels / Q000235:genetics* / Q000378:metabolism; D024683:Potassium Channels, Tandem Pore Domain; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D014981:Xenopus
D018076:DNA, Complementary; C431132:KCNK15 protein, human; C498655:KCNK9 protein, human; C486605:Kcnk15 protein, rat; C407082:Kcnk9 protein, rat; D009419:Nerve Tissue Proteins; D015221:Potassium Channels; D024683:Potassium Channels, Tandem Pore Domain; D012333:RNA, Messenger; C420132:potassium channel subfamily K member 3