Regional regulation of Filiform tongue papillae development by Ikkα/Irf6.
Non-gustatory filiform papillae play critical roles in helping to grip food, drawing food to the esophagus, cleaning the mouth, and spreading saliva. The molecular mechanisms of filiform tongue papillae development however are not fully understood.



We found Ikkα and Irf6 expression in developing tongue epithelium, and describe here specific tongue abnormalities in mice with mutation of these genes, indicating a role for Ikkα and Irf6 in filiform papillae development. Ikkα and Irf6 mutant tongues showed ectopic vertical epithelium at the midline, while lateral sides of mutant tongues adhered to the oral mucosa. Both the ectopic median vertical epithelium and adhered epithelium exhibited the presence of filiform tongue papillae, whereas epithelium between the median vertical epithelium and adhered tongue showed a loss of filiform tongue papillae. Timing of filiform papillae development was found to be slightly different between the midline and lateral regions of the wild-type tongue.



Filiform papillae thus develop through distinct molecular mechanisms between the regions of tongue dorsum in the medio-lateral axis, with some filiform papillae developing under the control of Ikkα and Irf6. Developmental Dynamics 245:937-946, 2016. © 2016 Wiley Periodicals, Inc.
Division of Oral Anatomy, Department of Oral Biological Science, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan.|Department of Craniofacial Development and Stem Cell Biology, Dental Institute, Kings College London, London, United Kingdom.
Maiko
M
Kawasaki
Division of Oral Anatomy, Department of Oral Biological Science, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan.|Department of Craniofacial Development and Stem Cell Biology, Dental Institute, Kings College London, London, United Kingdom.|Oral Life Science, Research Center for Advanced Oral Science, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan.
Katsushige
K
Kawasaki
Department of Craniofacial Development and Stem Cell Biology, Dental Institute, Kings College London, London, United Kingdom.
Shelly
S
Oommen
Department of Craniofacial Development and Stem Cell Biology, Dental Institute, Kings College London, London, United Kingdom.
James
J
Blackburn
Division of Oral Anatomy, Department of Oral Biological Science, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan.|Division of Oral and Maxillofacial Surgery, Department of Health Science, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan.
Momoko
M
Watanabe
Division of Oral Anatomy, Department of Oral Biological Science, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan.|Division of Oral and Maxillofacial Surgery, Department of Health Science, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan.
Takahiro
T
Nagai
Division of Oral Anatomy, Department of Oral Biological Science, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan.|Division of Oral and Maxillofacial Surgery, Department of Health Science, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan.
Atsushi
A
Kitamura
Division of Oral Anatomy, Department of Oral Biological Science, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan.|Oral Life Science, Research Center for Advanced Oral Science, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan.
Takeyasu
T
Maeda
Department of Molecular Carcinogenesis, UT MD Anderson Cancer Center, Smithville, Texas.
Bigang
B
Liu
Department of Signal Transduction in Tumor Cells, Max-Delbrück-Center for Molecular Medicine, Berlin, Germany.
Ruth
R
Schmidt-Ullrich
Division of Cellular and Molecular Biology, Institute of Medical Science, University of Tokyo, Minato-ku, Tokyo, Japan.
Taishin
T
Akiyama
Division of Cellular and Molecular Biology, Institute of Medical Science, University of Tokyo, Minato-ku, Tokyo, Japan.
Jun-Ichiro
J
Inoue
Faculty of Life Sciences and School of Dentistry, Manchester Academic Health Sciences Centre, University of Manchester, Manchester, United Kingdom.
Nigel L
NL
Hammond
Department of Craniofacial Development and Stem Cell Biology, Dental Institute, Kings College London, London, United Kingdom.
Paul T
PT
Sharpe
Division of Oral Anatomy, Department of Oral Biological Science, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan.|Department of Craniofacial Development and Stem Cell Biology, Dental Institute, Kings College London, London, United Kingdom.
Atsushi
A
Ohazama
D000818:Animals; D004848:Epithelium / Q000196:embryology / Q000378:metabolism* / Q000648:ultrastructure; D051550:I-kappa B Kinase / Q000235:genetics / Q000378:metabolism*; D007150:Immunohistochemistry; D017403:In Situ Hybridization; D050835:Interferon Regulatory Factors / Q000235:genetics / Q000378:metabolism*; D051379:Mice; D008822:Mice, Transgenic; D008855:Microscopy, Electron, Scanning; D014059:Tongue / Q000196:embryology* / Q000378:metabolism* / Q000648:ultrastructure
C528250:IRF6 protein, mouse; D050835:Interferon Regulatory Factors; C496564:Chuk protein, mouse; D051550:I-kappa B Kinase
Filiform papillae; Ikkα; Irf6