Increased noise sensitivity and altered inner ear MENA distribution in VASP?/? mice
- 2 October 2004
- journal article
- research article
- Published by Springer Science and Business Media LLC in Cell and tissue research
- Vol. 318 (3), 493-502
- https://doi.org/10.1007/s00441-004-0964-9
Abstract
Vasodilator-stimulated phosphoprotein (VASP) and mammalian-enabled protein (MENA) share similar cellular localisation and functions (signal transduction pathways, regulation of actin cytoskeleton dynamics). Functional substitution and compensation among Ena/VASP proteins have been proposed as the reason for the absence of major morphological and functional deficits in VASP−/− mice. The aim of this study was to investigate VASP expression in the mouse cochlea, to analyse cochlear function in VASP−/− mice compared with wildtype mice, and to analyse cochlear MENA distribution taking into account that MENA protein might compensate VASP loss in the cochlea of VASP−/− mice. We confirmed specific VASP expression in the pillar cells of the mice organ of Corti as previously reported for rat cochlea. By analysing the hearing function in VASP−/− mice, we found no differences in auditory brainstem responses and distortion product otoacoustic emissions from those of wildtype mice but evidence for an increased noise sensitivity at lower frequencies. When MENA protein levels in cochlea tissue were tested in mutant and wildtype mice by Western blot analysis, no significant differences were found, as was also seen with regard to MENA mRNA levels in laser-microdissected single pillar cells. Most surprisingly, however, MENA protein was absent in pillar cells of VASP−/− mice, whereas it was detected in other cochlear cells. The finding of a cell-specific, and not organ-specific, redundancy of MENA protein expression noted for the first time in VASP−/− mice is proposed as the reason for the observed distinct cochlear phenotype.Keywords
This publication has 31 references indexed in Scilit:
- Ena/VASP Proteins: Regulators of the Actin Cytoskeleton and Cell MigrationAnnual Review of Cell and Developmental Biology, 2003
- Abl Interactor 1 Promotes Tyrosine 296 Phosphorylation of Mammalian Enabled (Mena) by c-Abl KinasePublished by Elsevier BV ,2003
- Increased Spreading, Rac/p21-activated Kinase (PAK) Activity, and Compromised Cell Motility in Cells Deficient in Vasodilator-stimulated Phosphoprotein (VASP)Journal of Biological Chemistry, 2002
- How well do we understand the cochlea?Trends in Neurosciences, 1998
- Transient expression of NMDA receptors during rearrangement of AMPA-receptor-expressing fibers in the developing inner earCell and tissue research, 1996
- Cloning of the VASP (Vasodilator-Stimulated Phosphoprotein) Genes in Human and Mouse: Structure, Sequence, and Chromosomal LocalizationGenomics, 1996
- Mapping the cochlear partition’s stiffness to its cellular architectureThe Journal of the Acoustical Society of America, 1994
- Microtubule rearrangement and bending during assembly of large curved microtubule bundles in mouse cochlear epithelial cellsCell Motility, 1993
- Microtubules of Guinea Pig Cochlear Epithelial CellsActa Oto-Laryngologica, 1991
- Purification of a vasodilator‐regulated phosphoprotein from human plateletsEuropean Journal of Biochemistry, 1989