Dynamic expression of COUP-TFI and COUP-TFII during development and functional maturation of the mouse inner ear.
COUP-TFs (chicken ovalbumin upstream promoter-transcription factors) are orphan members of the nuclear receptor superfamily of ligand-activated receptors for which their ligands have not been identified. The two mammalian proteins, COUP-TFI and COUP-TFII, share 80% sequence identity and regulate many aspects of mammalian development and differentiation. In this report, we systemically examined the temporal and spatial expression of COUP-TFI and COUP-TFII transcripts and, for the first time, their protein during development and functional maturation of the cochlea. Both COUP-TFI and COUP-TFII were expressed early in the developing otic vesicle. COUP-TFI expression correlated with the differentiation of hair cells and support cells in the organ of Corti, whereas COUP-TFII expression was down-regulated with differentiation of the organ of Corti. Furthermore, we report for the first time, that the generally nuclear COUP-TFI receptor protein was localized in the cytoplasm of maturing hair cells and pillar cells. Collectively, although COUP-TFI and COUP-TFII are homologues, the expression of each orphan receptor has a restricted and dynamic expression during cochlea development particularly during patterning and differentiation of the cochlear structures.
Tang
Louisa S
LS
Huffington Center on Aging, Baylor College of Medicine, Houston, TX 77030, USA.
Alger
Heather M
HM
Lin
Feng
F
Pereira
Fred A
FA
D000818:Animals; D051838:COUP Transcription Factor I; D051837:COUP Transcription Factor II; D051836:COUP Transcription Factors; D002454:Cell Differentiation; D002467:Cell Nucleus / Q000378:metabolism; D003051:Cochlea / Q000196:embryology; D004268:DNA-Binding Proteins / Q000096:biosynthesis*; D007758:Ear, Inner / Q000196:embryology*; D004847:Epithelial Cells / Q000166:cytology*; D018507:Gene Expression Regulation, Developmental; D005838:Genotype; D006198:Hair Cells, Auditory; D007150:Immunohistochemistry; D017403:In Situ Hybridization; D051379:Mice; D008953:Models, Anatomic; D009925:Organ of Corti / Q000196:embryology* / Q000378:metabolism; D011987:Receptors, Steroid / Q000096:biosynthesis*; D013997:Time Factors; D014157:Transcription Factors / Q000096:biosynthesis*
D051838:COUP Transcription Factor I; D051837:COUP Transcription Factor II; D051836:COUP Transcription Factors; D004268:DNA-Binding Proteins; C497590:Nr2f1 protein, mouse; C497587:Nr2f2 protein, mouse; D011987:Receptors, Steroid; D014157:Transcription Factors