TY - JOUR
T1 - Diversity of Ca2+-activated K+ channel transcripts in inner ear hair cells
AU - Beisel, Kirk W.
AU - Rocha-Sanchez, Sonia M.
AU - Ziegenbein, Sylvia J.
AU - Morris, Ken A.
AU - Kai, Chikatoshi
AU - Kawai, Jun
AU - Carninci, Piero
AU - Hayashizaki, Yoshihide
AU - Davis, Robin L.
N1 - Funding Information:
This investigation was supported by research grants from the USPHS National Institute on Deafness and Other Communication Disorders grants R01 DC04279 (K.W.B.), R01 DC05009 (K.W.B.), and the National Organization for Hearing Research (S.M.R-S.), a research grant for the RIKEN Genome Exploration Research Project from the Ministry of Education, Culture, Sports, Science and Technology of the Japanese Government (Y.H.), and a grant of the Genome Network Project from the Ministry of Education, Culture, Sports, Science and Technology, Japan. We thank Dr. Bernd Fritzsch for his help in the imaging of whole mount samples and review and critique of the manuscript.
PY - 2007/1/15
Y1 - 2007/1/15
N2 - Hair cells express a complement of ion channels, representing shared and distinct channels that confer distinct electrophysiological signatures for each cell. This diversity is generated by the use of alternative splicing in the α subunit, formation of heterotetrameric channels, and combinatorial association with β subunits. These channels are thought to play a role in the tonotopic gradient observed in the mammalian cochlea. Mouse Kcnma1 transcripts, 5′ and 3′ ESTs, and genomic sequences were examined for the utilization of alternative splicing in the mouse transcriptome. Comparative genomic analyses investigated the conservation of KCNMA1 splice sites. Genomes of mouse, rat, human, opossum, chicken, frog and zebrafish established that the exon-intron structure and mechanism of KCNMA1 alternative splicing were highly conserved with 6-7 splice sites being utilized. The murine Kcnma1 utilized 6 out of 7 potential splice sites. RT-PCR experiments using murine gene-specific oligonucleotide primers analyzed the scope and variety of Kcnma1 and Kcnmb1-4 expression profiles in the cochlea and inner ear hair cells. In the cochlea splice variants were present representing sites 3, 4, 6, and 7, while site 1 was insertionless and site 2 utilized only exon 10. However, site 5 was not present. Detection of KCNMA1 transcripts and protein exhibited a quantitative longitudinal gradient with a reciprocal gradient found between inner and outer hair cells. Differential expression was also observed in the usage of the long form of the carboxy-terminus tail. These results suggest that a diversity of splice variants exist in rodent cochlear hair cells and this diversity is similar to that observed for non-mammalian vertebrate hair cells, such as chicken and turtle.
AB - Hair cells express a complement of ion channels, representing shared and distinct channels that confer distinct electrophysiological signatures for each cell. This diversity is generated by the use of alternative splicing in the α subunit, formation of heterotetrameric channels, and combinatorial association with β subunits. These channels are thought to play a role in the tonotopic gradient observed in the mammalian cochlea. Mouse Kcnma1 transcripts, 5′ and 3′ ESTs, and genomic sequences were examined for the utilization of alternative splicing in the mouse transcriptome. Comparative genomic analyses investigated the conservation of KCNMA1 splice sites. Genomes of mouse, rat, human, opossum, chicken, frog and zebrafish established that the exon-intron structure and mechanism of KCNMA1 alternative splicing were highly conserved with 6-7 splice sites being utilized. The murine Kcnma1 utilized 6 out of 7 potential splice sites. RT-PCR experiments using murine gene-specific oligonucleotide primers analyzed the scope and variety of Kcnma1 and Kcnmb1-4 expression profiles in the cochlea and inner ear hair cells. In the cochlea splice variants were present representing sites 3, 4, 6, and 7, while site 1 was insertionless and site 2 utilized only exon 10. However, site 5 was not present. Detection of KCNMA1 transcripts and protein exhibited a quantitative longitudinal gradient with a reciprocal gradient found between inner and outer hair cells. Differential expression was also observed in the usage of the long form of the carboxy-terminus tail. These results suggest that a diversity of splice variants exist in rodent cochlear hair cells and this diversity is similar to that observed for non-mammalian vertebrate hair cells, such as chicken and turtle.
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U2 - 10.1016/j.gene.2006.07.023
DO - 10.1016/j.gene.2006.07.023
M3 - Article
C2 - 17097837
AN - SCOPUS:33845536762
VL - 386
SP - 11
EP - 23
JO - Gene
JF - Gene
SN - 0378-1119
IS - 1-2
ER -