Hair cell development in vivo and in vitro: Analysis by using a monoclonal antibody specific to hair cells in the chick inner ear

2002 ◽  
Vol 445 (2) ◽  
pp. 176-198
Author(s):  
Kenji Kondo ◽  
Hiroshi Sagara ◽  
Kazushige Hirosawa ◽  
Kimitaka Kaga ◽  
Satsuki Matsushima ◽  
...  
Keyword(s):  
Monoclonal Antibody ◽  
Hair Cell ◽  
Inner Ear ◽  
Hair Cells ◽  
Cell Development ◽  
Vitro Analysis ◽  
In Vitro Analysis

scholarly journals SoxC transcription factors are essential for the development of the inner ear

2015 ◽  
Vol 112 (45) ◽  
pp. 14066-14071 ◽  
Author(s):  
Ksenia Gnedeva ◽  
A. J. Hudspeth
Keyword(s):  
Transcription Factors ◽  
Hair Cell ◽  
Inner Ear ◽  
Hair Cells ◽  
Supporting Cell ◽  
Sensory Epithelia ◽  
Enhanced Expression ◽  
Mechanosensory Receptors

Hair cells, the mechanosensory receptors of the inner ear, underlie the senses of hearing and balance. Adult mammals cannot adequately replenish lost hair cells, whose loss often results in deafness or balance disorders. To determine the molecular basis of this deficiency, we investigated the development of a murine vestibular organ, the utricle. Here we show that two members of the SoxC family of transcription factors, Sox4 and Sox11, are down-regulated after the epoch of hair cell development. Conditional ablation of SoxC genes in vivo results in stunted sensory organs of the inner ear and loss of hair cells. Enhanced expression of SoxC genes in vitro conversely restores supporting cell proliferation and the production of new hair cells in adult sensory epithelia. These results imply that SoxC genes govern hair cell production and thus advance these genes as targets for the restoration of hearing and balance.

In Vitro Analysis of Murine B-Cell Development

1985 ◽  
Vol 3 (1) ◽  
pp. 213-235 ◽  
Author(s):  
C Whitlock ◽  
K Denis ◽  
D Robertson ◽  
O Witte
Keyword(s):  
B Cell ◽  
Cell Development ◽  
B Cell Development ◽  
Vitro Analysis ◽  
In Vitro Analysis

scholarly journals In vitro analysis of elongation and termination by mutant RNA polymerases with altered termination behavior.

1996 ◽  
Vol 16 (11) ◽  
pp. 6468-6476 ◽  
Author(s):  
S A Shaaban ◽  
E V Bobkova ◽  
D M Chudzik ◽  
B D Hall
Keyword(s):  
Rna Polymerase Iii ◽  
Multiple Roles ◽  
Wild Type ◽  
Protein Motifs ◽  
Study Support ◽  
Vitro Analysis ◽  
Pol Iii ◽  
In Vitro Analysis

We have studied the in vitro elongation and termination properties of several yeast RNA polymerase III (pol III) mutant enzymes that have altered in vivo termination behavior (S. A. Shaaban, B. M. Krupp, and B. D. Hall, Mol. Cell. Biol. 15:1467-1478, 1995). The pattern of completed-transcript release was also characterized for three of the mutant enzymes. The mutations studied occupy amino acid regions 300 to 325, 455 to 521, and 1061 to 1082 of the RET1 protein (P. James, S. Whelen, and B. D. Hall, J. Biol. Chem. 266:5616-5624, 1991), the second largest subunit of yeast RNA pol III. In general, mutant enzymes which have increased termination require a longer time to traverse a template gene than does wild-type pol III; the converse holds true for most decreased-termination mutants. One increased-termination mutant (K310T I324K) was faster and two reduced termination mutants (K512N and T455I E478K) were slower than the wild-type enzyme. In most cases, these changes in overall elongation kinetics can be accounted for by a correspondingly longer or shorter dwell time at pause sites within the SUP4 tRNA(Tyr) gene. Of the three mutants analyzed for RNA release, one (T455I) was similar to the wild type while the two others (T455I E478K and E478K) bound the completed SUP4 pre-tRNA more avidly. The results of this study support the view that termination is a multistep pathway in which several different regions of the RET1 protein are actively involved. Region 300 to 325 likely affects a step involved in RNA release, while the Rif homology region, amino acids 455 to 521, interacts with the nascent RNA 3' end. The dual effects of several mutations on both elongation kinetics and RNA release suggest that the protein motifs affected by them have multiple roles in the steps leading to transcription termination.

Multifactorial Regulation of Cardiac Gene Expression: an In Vivo and In Vitro Analysis

1995 ◽  
Vol 752 (1 Cardiac Growt) ◽  
pp. 370-386 ◽  
Author(s):  
J. L. SAMUEL ◽  
I. DUBUS ◽  
F. FARHADIAN ◽  
F. MAROTTE ◽  
P. OLIVIERO ◽  
...  
Keyword(s):  
Gene Expression ◽  
Cardiac Gene Expression ◽  
Cardiac Gene ◽  
Vitro Analysis ◽  
In Vitro Analysis

scholarly journals A Critical E-box in Barhl1 3′ Enhancer Is Essential for Auditory Hair Cell Differentiation

Cells ◽  
2019 ◽  
Vol 8 (5) ◽  
pp. 458 ◽  
Author(s):  
Kun Hou ◽  
Hui Jiang ◽  
Md. Rezaul Karim ◽  
Chao Zhong ◽  
Zhouwen Xu ◽  
...  
Keyword(s):  
Cell Differentiation ◽  
Hair Cell ◽  
Hair Cells ◽  
Embryonic Stem ◽  
Cell Development ◽  
Homologous Gene ◽  
Auditory Hair Cells ◽  
E Box ◽  
Hair Cell Differentiation

Barhl1, a mouse homologous gene of Drosophila BarH class homeobox genes, is highly expressed within the inner ear and crucial for the long-term maintenance of auditory hair cells that mediate hearing and balance, yet little is known about the molecular events underlying Barhl1 regulation and function in hair cells. In this study, through data mining and in vitro report assay, we firstly identified Barhl1 as a direct target gene of Atoh1 and one E-box (E3) in Barhl1 3’ enhancer is crucial for Atoh1-mediated Barhl1 activation. Then we generated a mouse embryonic stem cell (mESC) line carrying disruptions on this E3 site E-box (CAGCTG) using CRISPR/Cas9 technology and this E3 mutated mESC line is further subjected to an efficient stepwise hair cell differentiation strategy in vitro. Disruptions on this E3 site caused dramatic loss of Barhl1 expression and significantly reduced the number of induced hair cell-like cells, while no affections on the differentiation toward early primitive ectoderm-like cells and otic progenitors. Finally, through RNA-seq profiling and gene ontology (GO) enrichment analysis, we found that this E3 box was indispensable for Barhl1 expression to maintain hair cell development and normal functions. We also compared the transcriptional profiles of induced cells from CDS mutated and E3 mutated mESCs, respectively, and got very consistent results except the Barhl1 transcript itself. These observations indicated that Atoh1-mediated Barhl1 expression could have important roles during auditory hair cell development. In brief, our findings delineate the detail molecular mechanism of Barhl1 expression regulation in auditory hair cell differentiation.

scholarly journals Calcium Modulates the Frequency and Amplitude of Spontaneous Otoacoustic Emissions in the Bobtail Skink

2004 ◽  
Vol 92 (5) ◽  
pp. 2685-2693 ◽  
Author(s):  
Geoffrey A. Manley ◽  
Ulrike Sienknecht ◽  
Christine Köppl
Keyword(s):  
Hair Cell ◽  
Hair Cells ◽  
Otoacoustic Emissions ◽  
Calcium Concentration ◽  
Chelating Agent ◽  
Lizard Species ◽  
Spontaneous Otoacoustic Emissions ◽  
Active Processes

Active processes in the inner ear of lizards can be monitored using spontaneous otoacoustic emissions (SOAE) measured outside the eardrum. In the Australian bobtail lizard, SOAE are generated by an active motility process in the hair-cell bundle. This mechanism has been shown to be sensitive to the calcium-chelating agent 1,2-bis(o-aminophenoxy)ethane- N,N,N′,N′-tetraacetic acid and is presumed to be related to the calcium-sensitive transduction-channel motor implicated in other nonmammalian hair cell systems. In studies of frog saccular and turtle auditory papillar hair cells in vitro, the frequency and amplitude of bundle oscillations depend on the concentration of calcium in the bathing solutions. In the present study, the calcium concentration in the endolymph was changed in vivo in the Australian bobtail lizard Tiliqua rugosa, and SOAE were monitored. Glass pipettes with large tips and containing different calcium concentrations in their fluids were introduced into scala media, and their contents were allowed to passively flow into the endolymph. Low calcium concentrations resulted in a downward shift in the frequency of SOAE spectral peaks and generally an increase in their amplitudes. Calcium concentrations >2 mM resulted in increases in frequency of SOAE peaks and generally a loss in amplitude. These frequency shifts were consistent with in vitro data on the frequencies and amplitudes of spontaneous oscillation of hair cell bundles and thus also implicate calcium ions in the generation of active motility in nonmammalian hair cells. The data also suggest that in this lizard species, the ionic calcium concentration in the cochlear endolymph is ≥1 mM.

Sign in / Sign up

Export Citation Format

Share Document