title: Expression of forkhead box transcription factor genes Foxp1 and Foxp2 during jaw development.
abstract: Development of the face is regulated by a large number of genes that are expressed in temporally and spatially specific patterns. While significant progress has been made on characterizing the genes that operate in the oral region of the face, those regulating development of the aboral (lateral) region remain largely unknown. Recently, we discovered that transcription factors LIM homeobox (LHX) 6 and LHX8, which are key regulators of oral development, repressed the expression of the genes encoding forkhead box transcription factors, Foxp1 and Foxp2, in the oral region. To gain insights into the potential role of the Foxp genes in region-specific development of the face, we examined their expression patterns in the first pharyngeal arch (primordium for the jaw) of mouse embryos at a high spatial and temporal resolution. Foxp1 and Foxp2 were preferentially expressed in the aboral and posterior parts of the first pharyngeal arch, including the developing temporomandibular joint. Through double immunofluorescence and double fluorescent RNA in situ hybridization, we found that Foxp1 was expressed in the progenitor cells for the muscle, bone, and connective tissue. Foxp2 was expressed in subsets of bone and connective tissue progenitors but not in the myoblasts. Neither gene was expressed in the dental mesenchyme nor in the oral half of the palatal shelf undergoing extensive growth and morphogenesis. Together, we demonstrated for the first time that Foxp1 and Foxp2 are expressed during craniofacial development. Our data suggest that the Foxp genes may regulate development of the aboral and posterior regions of the jaw.
authors.affiliation: Department of Basic Science and Craniofacial Biology, New York University College of Dentistry, 345 East 24th Street, New York, NY 10010 United States.
authors.forename: Jeffry M
authors.initials: JM
authors.lastname: Cesario
authors.affiliation: Department of Orthodontics, New York University College of Dentistry, 345 East 24th Street, New York, NY 10010 United States.
authors.forename: Asma A
authors.initials: AA
authors.lastname: Almaidhan
authors.affiliation: Department of Basic Science and Craniofacial Biology, New York University College of Dentistry, 345 East 24th Street, New York, NY 10010 United States. Electronic address: jj78@nyu.edu.
authors.forename: Juhee
authors.initials: J
authors.lastname: Jeong
mesh_terms: D000818:Animals; D047108:Embryonic Development / Q000235:genetics; D051858:Forkhead Transcription Factors / Q000096:biosynthesis / Q000235:genetics*; D018507:Gene Expression Regulation, Developmental; D007568:Jaw / Q000196:embryology* / Q000378:metabolism; D008445:Maxillofacial Development / Q000235:genetics*; D051379:Mice; D012097:Repressor Proteins / Q000096:biosynthesis / Q000235:genetics*
chemical_list: D051858:Forkhead Transcription Factors; C432917:Foxp1 protein, mouse; C432918:Foxp2 protein, mouse; D012097:Repressor Proteins
keywords: Craniofacial development; Foxp1; Foxp2; Mouse; Pharyngeal arch; Temporomandibular joint