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Gipc3 mutations associated with audiogenic seizures and sensorineural hearing loss in mouse and human.

Charizopoulou N, Lelli A, Schraders M, Ray K, Hildebrand MS, Ramesh A, Srisailapathy CR, Oostrik J, Admiraal RJ, Neely HR, Latoche JR, Smith RJ, Northup JK, Kremer H, Holt JR, Noben-Trauth K - Nat Commun (2011)

Bottom Line: A missense mutation in the PDZ domain has an attenuating effect on mechanotransduction and the acquisition of mature inner hair cell potassium currents.The Gipc3(343A) allele disrupts the structure of the stereocilia bundle and affects long-term function of auditory hair cells and spiral ganglion neurons.Our study suggests a pivotal role of Gipc3 in acoustic signal acquisition and propagation in cochlear hair cells.

View Article: PubMed Central - PubMed

Affiliation: Section on Neurogenetics, Laboratory of Molecular Biology, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Rockville, Maryland 20850, USA.

ABSTRACT
Sensorineural hearing loss affects the quality of life and communication of millions of people, but the underlying molecular mechanisms remain elusive. Here, we identify mutations in Gipc3 underlying progressive sensorineural hearing loss (age-related hearing loss 5, ahl5) and audiogenic seizures (juvenile audiogenic monogenic seizure 1, jams1) in mice and autosomal recessive deafness DFNB15 and DFNB95 in humans. Gipc3 localizes to inner ear sensory hair cells and spiral ganglion. A missense mutation in the PDZ domain has an attenuating effect on mechanotransduction and the acquisition of mature inner hair cell potassium currents. Magnitude and temporal progression of wave I amplitude of afferent neurons correlate with susceptibility and resistance to audiogenic seizures. The Gipc3(343A) allele disrupts the structure of the stereocilia bundle and affects long-term function of auditory hair cells and spiral ganglion neurons. Our study suggests a pivotal role of Gipc3 in acoustic signal acquisition and propagation in cochlear hair cells.

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Positional cloning of the ahl5 locus.(a) ABR thresholds at click (orange), 8 (green), 16 (purple) and 32 kHz (red) of congenic BLSW.CAST-+/ahl5 (n=83) and BLSW.CAST-ahl5/ahl5 (n=59) mice at 8 weeks of age. Hearing thresholds (dBSPL) were significantly elevated for the BLSW.CAST-ahl5/ahl5 animals compared with BLSW.CAST-+/ahl5 (ANOVA, P<0.001). Data are given as mean±s.d. (b) The ahl5 95% confidence interval (CI) on chromosome 10 (MMU10) defined by markers D10Mit20 and D10Mit95 is shown. Refined genotyping of two congenic lines 10.R and 10.2 delimited the ahl5 critical interval in a 2.19 Mbp region (red box) defined by markers D10Ntra205 and D10Ntra222. Blue bars at the bottom of the map represent the congenic segments from CAST/EiJ introgressed onto the BLSW genetic background (red lines). The jams1 locus delimited by the gene Basigin (Bsg) and marker D10Mit140 on MMU10 is shown (orange box)12. Physical location of Gipc3 within the ahl5 interval is given. Position of the markers is given in kilobase pairs (kbp). (c) Gipc3 has six exons and is predicted to encode a 297 amino-acid protein with a central PDZ domain (blue box) flanked by amino- and C-terminal GIPC homologous domains GH1 and GH2 (grey boxes). Position of the mutation (red annotation) and polyclonal antisera Pb867, Pb869 and Pb877 (green boxes) is shown. (d) Sequencing chromatograms demonstrating the 343G>A transition in wild-type (left) and mutant (right) are shown. The nucleotide (A, adenine) and amino acid (Arg, arginine) changes are shown in red. (e) ABR thresholds (dBSPL) at click (orange), 8 (green), 16 (purple) and 32 kHz (red) of NIH Swiss homozygous for the wild-type (343G/G; n=9) and mutant (343A/A; n=9) Gipc3 alleles. Homozygous (343A/A) NIH Swiss at 6 weeks of age had significantly higher thresholds at all tested stimuli (P<0.0001; ANOVA). Data are given as mean±s.d. (f) ClustalW alignment of the amino-acid sequence of Gipc3 homologues and the location of the Gly115Arg relative to the secondary structure, obtained from the GIPC2 crystal structure (DOI:10.2210/pdb3gge/pdb) is shown. Gly115 maps to a loop (yellow), connecting to β strands, βB (green) and βC (blue).
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f1: Positional cloning of the ahl5 locus.(a) ABR thresholds at click (orange), 8 (green), 16 (purple) and 32 kHz (red) of congenic BLSW.CAST-+/ahl5 (n=83) and BLSW.CAST-ahl5/ahl5 (n=59) mice at 8 weeks of age. Hearing thresholds (dBSPL) were significantly elevated for the BLSW.CAST-ahl5/ahl5 animals compared with BLSW.CAST-+/ahl5 (ANOVA, P<0.001). Data are given as mean±s.d. (b) The ahl5 95% confidence interval (CI) on chromosome 10 (MMU10) defined by markers D10Mit20 and D10Mit95 is shown. Refined genotyping of two congenic lines 10.R and 10.2 delimited the ahl5 critical interval in a 2.19 Mbp region (red box) defined by markers D10Ntra205 and D10Ntra222. Blue bars at the bottom of the map represent the congenic segments from CAST/EiJ introgressed onto the BLSW genetic background (red lines). The jams1 locus delimited by the gene Basigin (Bsg) and marker D10Mit140 on MMU10 is shown (orange box)12. Physical location of Gipc3 within the ahl5 interval is given. Position of the markers is given in kilobase pairs (kbp). (c) Gipc3 has six exons and is predicted to encode a 297 amino-acid protein with a central PDZ domain (blue box) flanked by amino- and C-terminal GIPC homologous domains GH1 and GH2 (grey boxes). Position of the mutation (red annotation) and polyclonal antisera Pb867, Pb869 and Pb877 (green boxes) is shown. (d) Sequencing chromatograms demonstrating the 343G>A transition in wild-type (left) and mutant (right) are shown. The nucleotide (A, adenine) and amino acid (Arg, arginine) changes are shown in red. (e) ABR thresholds (dBSPL) at click (orange), 8 (green), 16 (purple) and 32 kHz (red) of NIH Swiss homozygous for the wild-type (343G/G; n=9) and mutant (343A/A; n=9) Gipc3 alleles. Homozygous (343A/A) NIH Swiss at 6 weeks of age had significantly higher thresholds at all tested stimuli (P<0.0001; ANOVA). Data are given as mean±s.d. (f) ClustalW alignment of the amino-acid sequence of Gipc3 homologues and the location of the Gly115Arg relative to the secondary structure, obtained from the GIPC2 crystal structure (DOI:10.2210/pdb3gge/pdb) is shown. Gly115 maps to a loop (yellow), connecting to β strands, βB (green) and βC (blue).

Mentions: To genetically refine the ahl5 region, we generated two congenic lines, 10.R and 10.2, by serial backcrossing normal hearing BLSW.CAST-+/ahl5 progeny to BLSW mice. At generation N8 and higher, there was a significant correlation between segregation of ahl5 alleles and auditory brain stem response (ABR) thresholds (Fig. 1a). Recombination events delimited the ahl5 interval to a 2.19 Mbp region (Fig. 1b and Supplementary Fig. S1). We sequenced 735 of the 831 coding exons in BLSW genomic DNA and identified one nucleotide substitution, which was a guanine to adenine transition in exon 2 of the Gipc3 gene (c.343G>A; Fig. 1c,d). The mutation was absent in 14 inbred and four heterogeneous mouse strains (NMRI, Swiss Webster, CF1 and ICR). However, the 343G/A alleles segregated in mice of the National Institutes of Health (NIH) Swiss founder strain and showed significant correlation with hearing status. Gipc3343A/A homozygotes had impaired hearing (95±7 dBSPL at 16 kHz), whereas NIH Swiss mice homozygous at the wild-type allele (Gipc3343G/G) exhibited normal hearing (16±5 dBSPL at 16 kHz; Fig. 1e). The missense mutation replaced a glycine with an arginine at position 115 (Gly115Arg) located within the PDZ domain (aa107–174). The Gly115 residue is highly conserved, showing 100% identity in all published GIPC protein sequences in animals and plants (Fig. 1f).


Gipc3 mutations associated with audiogenic seizures and sensorineural hearing loss in mouse and human.

Charizopoulou N, Lelli A, Schraders M, Ray K, Hildebrand MS, Ramesh A, Srisailapathy CR, Oostrik J, Admiraal RJ, Neely HR, Latoche JR, Smith RJ, Northup JK, Kremer H, Holt JR, Noben-Trauth K - Nat Commun (2011)

Positional cloning of the ahl5 locus.(a) ABR thresholds at click (orange), 8 (green), 16 (purple) and 32 kHz (red) of congenic BLSW.CAST-+/ahl5 (n=83) and BLSW.CAST-ahl5/ahl5 (n=59) mice at 8 weeks of age. Hearing thresholds (dBSPL) were significantly elevated for the BLSW.CAST-ahl5/ahl5 animals compared with BLSW.CAST-+/ahl5 (ANOVA, P<0.001). Data are given as mean±s.d. (b) The ahl5 95% confidence interval (CI) on chromosome 10 (MMU10) defined by markers D10Mit20 and D10Mit95 is shown. Refined genotyping of two congenic lines 10.R and 10.2 delimited the ahl5 critical interval in a 2.19 Mbp region (red box) defined by markers D10Ntra205 and D10Ntra222. Blue bars at the bottom of the map represent the congenic segments from CAST/EiJ introgressed onto the BLSW genetic background (red lines). The jams1 locus delimited by the gene Basigin (Bsg) and marker D10Mit140 on MMU10 is shown (orange box)12. Physical location of Gipc3 within the ahl5 interval is given. Position of the markers is given in kilobase pairs (kbp). (c) Gipc3 has six exons and is predicted to encode a 297 amino-acid protein with a central PDZ domain (blue box) flanked by amino- and C-terminal GIPC homologous domains GH1 and GH2 (grey boxes). Position of the mutation (red annotation) and polyclonal antisera Pb867, Pb869 and Pb877 (green boxes) is shown. (d) Sequencing chromatograms demonstrating the 343G>A transition in wild-type (left) and mutant (right) are shown. The nucleotide (A, adenine) and amino acid (Arg, arginine) changes are shown in red. (e) ABR thresholds (dBSPL) at click (orange), 8 (green), 16 (purple) and 32 kHz (red) of NIH Swiss homozygous for the wild-type (343G/G; n=9) and mutant (343A/A; n=9) Gipc3 alleles. Homozygous (343A/A) NIH Swiss at 6 weeks of age had significantly higher thresholds at all tested stimuli (P<0.0001; ANOVA). Data are given as mean±s.d. (f) ClustalW alignment of the amino-acid sequence of Gipc3 homologues and the location of the Gly115Arg relative to the secondary structure, obtained from the GIPC2 crystal structure (DOI:10.2210/pdb3gge/pdb) is shown. Gly115 maps to a loop (yellow), connecting to β strands, βB (green) and βC (blue).
© Copyright Policy - open-access
Related In: Results  -  Collection

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Show All Figures
getmorefigures.php?uid=PMC3105340&req=5

f1: Positional cloning of the ahl5 locus.(a) ABR thresholds at click (orange), 8 (green), 16 (purple) and 32 kHz (red) of congenic BLSW.CAST-+/ahl5 (n=83) and BLSW.CAST-ahl5/ahl5 (n=59) mice at 8 weeks of age. Hearing thresholds (dBSPL) were significantly elevated for the BLSW.CAST-ahl5/ahl5 animals compared with BLSW.CAST-+/ahl5 (ANOVA, P<0.001). Data are given as mean±s.d. (b) The ahl5 95% confidence interval (CI) on chromosome 10 (MMU10) defined by markers D10Mit20 and D10Mit95 is shown. Refined genotyping of two congenic lines 10.R and 10.2 delimited the ahl5 critical interval in a 2.19 Mbp region (red box) defined by markers D10Ntra205 and D10Ntra222. Blue bars at the bottom of the map represent the congenic segments from CAST/EiJ introgressed onto the BLSW genetic background (red lines). The jams1 locus delimited by the gene Basigin (Bsg) and marker D10Mit140 on MMU10 is shown (orange box)12. Physical location of Gipc3 within the ahl5 interval is given. Position of the markers is given in kilobase pairs (kbp). (c) Gipc3 has six exons and is predicted to encode a 297 amino-acid protein with a central PDZ domain (blue box) flanked by amino- and C-terminal GIPC homologous domains GH1 and GH2 (grey boxes). Position of the mutation (red annotation) and polyclonal antisera Pb867, Pb869 and Pb877 (green boxes) is shown. (d) Sequencing chromatograms demonstrating the 343G>A transition in wild-type (left) and mutant (right) are shown. The nucleotide (A, adenine) and amino acid (Arg, arginine) changes are shown in red. (e) ABR thresholds (dBSPL) at click (orange), 8 (green), 16 (purple) and 32 kHz (red) of NIH Swiss homozygous for the wild-type (343G/G; n=9) and mutant (343A/A; n=9) Gipc3 alleles. Homozygous (343A/A) NIH Swiss at 6 weeks of age had significantly higher thresholds at all tested stimuli (P<0.0001; ANOVA). Data are given as mean±s.d. (f) ClustalW alignment of the amino-acid sequence of Gipc3 homologues and the location of the Gly115Arg relative to the secondary structure, obtained from the GIPC2 crystal structure (DOI:10.2210/pdb3gge/pdb) is shown. Gly115 maps to a loop (yellow), connecting to β strands, βB (green) and βC (blue).
Mentions: To genetically refine the ahl5 region, we generated two congenic lines, 10.R and 10.2, by serial backcrossing normal hearing BLSW.CAST-+/ahl5 progeny to BLSW mice. At generation N8 and higher, there was a significant correlation between segregation of ahl5 alleles and auditory brain stem response (ABR) thresholds (Fig. 1a). Recombination events delimited the ahl5 interval to a 2.19 Mbp region (Fig. 1b and Supplementary Fig. S1). We sequenced 735 of the 831 coding exons in BLSW genomic DNA and identified one nucleotide substitution, which was a guanine to adenine transition in exon 2 of the Gipc3 gene (c.343G>A; Fig. 1c,d). The mutation was absent in 14 inbred and four heterogeneous mouse strains (NMRI, Swiss Webster, CF1 and ICR). However, the 343G/A alleles segregated in mice of the National Institutes of Health (NIH) Swiss founder strain and showed significant correlation with hearing status. Gipc3343A/A homozygotes had impaired hearing (95±7 dBSPL at 16 kHz), whereas NIH Swiss mice homozygous at the wild-type allele (Gipc3343G/G) exhibited normal hearing (16±5 dBSPL at 16 kHz; Fig. 1e). The missense mutation replaced a glycine with an arginine at position 115 (Gly115Arg) located within the PDZ domain (aa107–174). The Gly115 residue is highly conserved, showing 100% identity in all published GIPC protein sequences in animals and plants (Fig. 1f).

Bottom Line: A missense mutation in the PDZ domain has an attenuating effect on mechanotransduction and the acquisition of mature inner hair cell potassium currents.The Gipc3(343A) allele disrupts the structure of the stereocilia bundle and affects long-term function of auditory hair cells and spiral ganglion neurons.Our study suggests a pivotal role of Gipc3 in acoustic signal acquisition and propagation in cochlear hair cells.

View Article: PubMed Central - PubMed

Affiliation: Section on Neurogenetics, Laboratory of Molecular Biology, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Rockville, Maryland 20850, USA.

ABSTRACT
Sensorineural hearing loss affects the quality of life and communication of millions of people, but the underlying molecular mechanisms remain elusive. Here, we identify mutations in Gipc3 underlying progressive sensorineural hearing loss (age-related hearing loss 5, ahl5) and audiogenic seizures (juvenile audiogenic monogenic seizure 1, jams1) in mice and autosomal recessive deafness DFNB15 and DFNB95 in humans. Gipc3 localizes to inner ear sensory hair cells and spiral ganglion. A missense mutation in the PDZ domain has an attenuating effect on mechanotransduction and the acquisition of mature inner hair cell potassium currents. Magnitude and temporal progression of wave I amplitude of afferent neurons correlate with susceptibility and resistance to audiogenic seizures. The Gipc3(343A) allele disrupts the structure of the stereocilia bundle and affects long-term function of auditory hair cells and spiral ganglion neurons. Our study suggests a pivotal role of Gipc3 in acoustic signal acquisition and propagation in cochlear hair cells.

Show MeSH
Related in: MedlinePlus