title: Functional role of TGF-β receptors during palatal fusion in vitro.
abstract: OBJECTIVE
  Reported expression patterns for TGF-β receptors (TβR-I, -II, and -III) during palatogenesis suggest that they play essential roles in the mechanisms leading to palatal fusion. The purpose of this study was to compare the functions of the three TβRs during palatal fusion.
  
  
  METHODS
  Using organ culture of mouse palatal shelves, expression levels of TβR-I, -II, and -III were suppressed by transfecting the siRNAs siTβR-I, -II, and -III, respectively. Phosphorylation of SMAD2 was examined as an indicator of downstream signalling via each TβR. Linkage between TGF-β signalling and critical events in palatal fusion led to the use of, MMP-13 expression as an outcome measure for the function of the TGF-β receptors.
  
  
  RESULTS
  The siRNA treatment decreased the expression level of each receptor by more than 85%. When treated with either siTβR-I or -II, palatal shelves at E13+72 h were not fused, with complete clefting in the anterior and posterior regions. The middle palatal region following treatment with either siTβR-I or -II had fusion from one-half or one-third of the palatal region. Treatment with siTβR-III resulted in a persistent midline seam of medial edge epithelium (MEE) in the anterior region with islands of persistent MEE in the middle and posterior regions of the midline. Treatment with all three siTβRs altered the pattern of SMAD2 phosphorylation. Palatal shelf cultures treated with siTβR-I or -II, but not -III, showed altered MMP-13 expression levels.
  
  
  CONCLUSIONS
  The ability to identify and recover MEE and palatal mesenchymal cells during palatal fusion will aid in the evaluation of the different mechanistic events regulated by each TβR during palatogenesis.
authors.affiliation: Department of Orthodontics, Nihon University School of Dentistry, 1-8-13 Kanda Surugadai, Chiyoda-ku, Tokyo 1018310, Japan; Dental Research Center, Nihon University School of Dentistry, 1-8-13 Kanda Surugadai, Chiyoda-ku, Tokyo 1018310, Japan. Electronic address: nakajima.akira@nihon-u.ac.jp.
authors.forename: Akira
authors.initials: A
authors.lastname: Nakajima
authors.affiliation: Department of Molecular and Experimental Medicine, The Scripps Research Institute, 10550 North Torrey Pines Road, BCC-239, La Jolla, CA 92037, USA.
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Ito
authors.affiliation: Department of Orthodontics and Dentofacial Orthopedics, Institute of Health Biosciences, Tokushima University Graduate School, 3-18-5 Kuramoto-cho, Tokushima 7708504, Japan.
authors.forename: Eiji
authors.initials: E
authors.lastname: Tanaka
authors.affiliation: Nihon University Graduate School of Dentistry, Nihon University, 1-8-13 Kanda Surugadai, Chiyoda-ku, Tokyo 1018310, Japan.
authors.forename: Remi
authors.initials: R
authors.lastname: Sano
authors.affiliation: Nihon University Graduate School of Dentistry, Nihon University, 1-8-13 Kanda Surugadai, Chiyoda-ku, Tokyo 1018310, Japan.
authors.forename: Yoko
authors.initials: Y
authors.lastname: Karasawa
authors.affiliation: Dental Research Center, Nihon University School of Dentistry, 1-8-13 Kanda Surugadai, Chiyoda-ku, Tokyo 1018310, Japan.
authors.forename: Masao
authors.initials: M
authors.lastname: Maeno
authors.affiliation: Dental Research Center, Nihon University School of Dentistry, 1-8-13 Kanda Surugadai, Chiyoda-ku, Tokyo 1018310, Japan.
authors.forename: Koichi
authors.initials: K
authors.lastname: Iwata
authors.affiliation: Department of Orthodontics, Nihon University School of Dentistry, 1-8-13 Kanda Surugadai, Chiyoda-ku, Tokyo 1018310, Japan; Dental Research Center, Nihon University School of Dentistry, 1-8-13 Kanda Surugadai, Chiyoda-ku, Tokyo 1018310, Japan.
authors.forename: Noriyoshi
authors.initials: N
authors.lastname: Shimizu
authors.affiliation: Department of Oral Biological and Medical Sciences, Faculty of Dentistry, University of British Columbia, 2194 Health Sciences Mall, Vancouver, BC, Canada V6T 1Z3.
authors.forename: Charles F
authors.initials: CF
authors.lastname: Shuler
mesh_terms: D000818:Animals; D015153:Blotting, Western; D005455:Fluorescent Antibody Technique; D066298:In Vitro Techniques; D047908:Intracellular Signaling Peptides and Proteins / Q000378:metabolism; D053509:Matrix Metalloproteinase 13 / Q000378:metabolism; D051379:Mice; D010159:Palate / Q000196:embryology* / Q000378:metabolism*; D010641:Phenotype; D010766:Phosphorylation; D034741:RNA, Small Interfering / Q000494:pharmacology*; D016601:RNA-Binding Proteins; D018125:Receptors, Transforming Growth Factor beta / Q000502:physiology*; D015398:Signal Transduction; D014162:Transfection
chemical_list: D047908:Intracellular Signaling Peptides and Proteins; D034741:RNA, Small Interfering; D016601:RNA-Binding Proteins; D018125:Receptors, Transforming Growth Factor beta; C485848:Snip1 protein, mouse; D053509:Matrix Metalloproteinase 13; C507081:Mmp13 protein, mouse
keywords: MMP-13 expression; Palatal development; SMAD2 phosphorylation; TGF-β receptor; TGF-β signalling; siRNA
references.citation: J Mol Histol. 2010 Dec;41(6):343-55
references.pmid: 20967564
references.citation: Dev Dyn. 2008 Oct;237(10):2716-25
references.pmid: 18697225
references.citation: Dev Dyn. 2007 Mar;236(3):791-801
references.pmid: 17295310
references.citation: EMBO J. 2001 Feb 1;20(3):480-90
references.pmid: 11157754
references.citation: Development. 1988;103 Suppl:41-60
references.pmid: 3074914
references.citation: Cell Signal. 2010 Aug;22(8):1163-74
references.pmid: 20153821
references.citation: Development. 2003 Nov;130(21):5269-80
references.pmid: 12975342
references.citation: Nat Genet. 1995 Dec;11(4):409-14
references.pmid: 7493021
references.citation: Development. 1992 Dec;116(4):1087-99
references.pmid: 1295731
references.citation: Nature. 2003 Oct 9;425(6958):577-84
references.pmid: 14534577
references.citation: Dev Dyn. 2003 Jul;227(3):387-94
references.pmid: 12815624
references.citation: Dev Cell. 2008 Aug;15(2):322-9
references.pmid: 18694570
references.citation: EMBO J. 2001 Apr 2;20(7):1663-73
references.pmid: 11285230
references.citation: Science. 1999 Mar 26;283(5410):2080-2
references.pmid: 10092230
references.citation: Cell. 2003 Jun 13;113(6):685-700
references.pmid: 12809600
references.citation: Dev Biol. 2005 Feb 1;278(1):193-202
references.pmid: 15649471
references.citation: Dev Biol. 2006 Sep 1;297(1):238-48
references.pmid: 16780827
references.citation: Dev Dyn. 1997 Jul;209(3):255-60
references.pmid: 9215640
references.citation: Hum Mol Genet. 2004 Jan 15;13(2):235-46
references.pmid: 14645201
references.citation: Int J Dev Biol. 1991 Dec;35(4):463-72
references.pmid: 1801871
references.citation: Mol Biol Cell. 2001 May;12(5):1457-66
references.pmid: 11359935
references.citation: Dev Biol. 1996 Mar 15;174(2):248-57
references.pmid: 8631497
references.citation: Dev Biol. 2006 Aug 15;296(2):298-314
references.pmid: 16806156
references.citation: J Clin Invest. 2012 Mar;122(3):873-85
references.pmid: 22326956
references.citation: Dev Biol. 2000 Apr 15;220(2):343-57
references.pmid: 10753521
references.citation: Hong Kong Med J. 2004 Oct;10(5):331-6
references.pmid: 15479962
references.citation: Dev Biol. 1996 Oct 10;179(1):297-302
references.pmid: 8873772
references.citation: Anat Embryol (Berl). 2000 Aug;202(2):129-41
references.pmid: 10985432
references.citation: Exp Biol Med (Maywood). 2009 May;234(5):483-91
references.pmid: 19234053
references.citation: Carcinogenesis. 2008 Feb;29(2):252-62
references.pmid: 17999987
references.citation: Cell Tissue Res. 2010 Apr;340(1):61-9
references.pmid: 20165883
references.citation: Int J Dev Biol. 1998 Sep;42(6):817-20
references.pmid: 9727838
references.citation: Nat Genet. 1995 Dec;11(4):415-21
references.pmid: 7493022
references.citation: Mol Cell Biol. 2003 Jun;23(12):4371-85
references.pmid: 12773577
references.citation: Nature. 1997 Dec 4;390(6659):465-71
references.pmid: 9393997
references.citation: Dev Biol. 2007 Jan 15;301(2):309-26
references.pmid: 16942766
references.citation: J Biol Chem. 2001 May 4;276(18):14588-96
references.pmid: 11278442
references.citation: Annu Rev Biochem. 1998;67:753-91
references.pmid: 9759503
references.citation: Mech Dev. 2008 Sep-Oct;125(9-10):874-82
references.pmid: 18586087
references.citation: J Dent Res. 2006 Dec;85(12):1074-84
references.pmid: 17122157
references.citation: Oral Dis. 2011 Nov;17(8):733-44
references.pmid: 21395922
references.citation: Lancet. 2009 Nov 21;374(9703):1773-85
references.pmid: 19747722
references.citation: Dev Dyn. 2006 Jul;235(7):1785-93
references.pmid: 16607645
references.citation: Int J Dev Biol. 2000 Jun;44(4):397-402
references.pmid: 10949049
references.citation: Dev Biol. 2007 Sep 15;309(2):193-207
references.pmid: 17698055
references.citation: J Biol Chem. 2013 May 10;288(19):13467-80
references.pmid: 23546880