TY - JOUR
T1 - Potential role of bFGF and retinoic acid in the regeneration of chicken cochlear hair cells
AU - Lee, Kenneth H.
AU - Cotanche, Douglas A.
N1 - Funding Information:
We would like to thank Elizabeth Messana for her technical assistance, Dan Orlow for his photographic assistance, and Maggie Muscato for providing use of the Olympus BX60 BMAX epifluorescence microscope. In addition, we would like to thank Dr. Wayne Vedekis for his generous gift of the antibody to RARfi. This work was supported by NIH Grant DC-01689 and a grant from NOHR.
PY - 1996/5
Y1 - 1996/5
N2 - Messenger RNAs (mRNA) of several growth factor receptors and related genes were examined with reverse transcriptase polymerase chain reaction (RT-PCR) in normal and noise-damaged chicken basilar papillae (BP). Analysis of the amplification products indicated the presence of mRNAs for epidermal growth factor receptor (EGFR), fibroblast growth factor receptor (FGFR), insulin-like growth factor receptor (IGFR), insulin receptor (IR), retinoic acid receptor beta (RARβ), retinoic acid receptor gamma (RXRγ), and basic fibroblast growth factor (BFGF) in both normal and noise-damaged BP. The RT-PCR products generated were characterized by size and sequencing analysis to confirm the identities of the target molecules. The subcellular localization of the mature protein analogs for EGFR, FGFR, IGFR, RARβ, and BFGF were identified using fluorescence immunocytochemistry and confocal laser scanning microscopy. These experiments indicated that EGFR is present in the stereociliary bundles in the hair cells, IGFR is not present in the cells of the BP, BFGF localizes in the nuclei of supporting cells in the BP, but not hair cells or hyaline cells, and that RARβ localizes in the perinuclear regions of hair cells. The subcellular distributions of these proteins were consistent in both noise-damaged and control BP. FGFR, in contrast, changed its distribution in the tissue after noise damage. In normal BP, FGFR is concentrated in the stereocilia of hair cells. However, in damaged regions of noise-exposed chick cochleae, FGFR is heavily expressed in the expanded apical regions of the supporting cells. These findings suggest that BFGF and retinoic acid may potentially play a role in the mechanisms which regulate the regeneration of chicken cochlear hair cells.
AB - Messenger RNAs (mRNA) of several growth factor receptors and related genes were examined with reverse transcriptase polymerase chain reaction (RT-PCR) in normal and noise-damaged chicken basilar papillae (BP). Analysis of the amplification products indicated the presence of mRNAs for epidermal growth factor receptor (EGFR), fibroblast growth factor receptor (FGFR), insulin-like growth factor receptor (IGFR), insulin receptor (IR), retinoic acid receptor beta (RARβ), retinoic acid receptor gamma (RXRγ), and basic fibroblast growth factor (BFGF) in both normal and noise-damaged BP. The RT-PCR products generated were characterized by size and sequencing analysis to confirm the identities of the target molecules. The subcellular localization of the mature protein analogs for EGFR, FGFR, IGFR, RARβ, and BFGF were identified using fluorescence immunocytochemistry and confocal laser scanning microscopy. These experiments indicated that EGFR is present in the stereociliary bundles in the hair cells, IGFR is not present in the cells of the BP, BFGF localizes in the nuclei of supporting cells in the BP, but not hair cells or hyaline cells, and that RARβ localizes in the perinuclear regions of hair cells. The subcellular distributions of these proteins were consistent in both noise-damaged and control BP. FGFR, in contrast, changed its distribution in the tissue after noise damage. In normal BP, FGFR is concentrated in the stereocilia of hair cells. However, in damaged regions of noise-exposed chick cochleae, FGFR is heavily expressed in the expanded apical regions of the supporting cells. These findings suggest that BFGF and retinoic acid may potentially play a role in the mechanisms which regulate the regeneration of chicken cochlear hair cells.
KW - Basic fibroblast growth factor
KW - Chicken
KW - Cochlea
KW - Epidermal growth factor receptor
KW - Fibroblast growth factor response
KW - Hair cell
KW - Insulin receptor
KW - Insulin-like growth factor receptor
KW - Regeneration
KW - Retinoic acid
KW - Retinoic acid receptor beta
KW - Retinoic acid receptor gamma
KW - Reverse transcriptase PCR
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U2 - 10.1016/0378-5955(95)00220-0
DO - 10.1016/0378-5955(95)00220-0
M3 - Article
C2 - 8789806
AN - SCOPUS:0030030195
SN - 0378-5955
VL - 94
SP - 1
EP - 13
JO - Hearing Research
JF - Hearing Research
IS - 1-2
ER -