Cesario Jeffry M, Almaidhan Asma A, Jeong Juhee
Department of Basic Science and Craniofacial Biology, New York University College of Dentistry, 345 East 24th Street, New York, NY 10010 United States.
Department of Orthodontics, New York University College of Dentistry, 345 East 24th Street, New York, NY 10010 United States.
Gene Expr Patterns. 2016 Mar;20(2):111-9. doi: 10.1016/j.gep.2016.03.001. Epub 2016 Mar 9.
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.
面部的发育受大量以时空特异性模式表达的基因调控。虽然在表征面部口腔区域中起作用的基因方面已取得重大进展，但调控口外（外侧）区域发育的基因在很大程度上仍不清楚。最近，我们发现作为口腔发育关键调节因子的转录因子LIM同源框（LHX）6和LHX8在口腔区域抑制了编码叉头框转录因子Foxp1和Foxp2的基因的表达。为了深入了解Foxp基因在面部区域特异性发育中的潜在作用，我们以高时空分辨率研究了它们在小鼠胚胎第一咽弓（颌的原基）中的表达模式。Foxp1和Foxp2优先在第一咽弓的口外和后部表达，包括发育中的颞下颌关节。通过双重免疫荧光和双重荧光RNA原位杂交，我们发现Foxp1在肌肉、骨骼和结缔组织的祖细胞中表达。Foxp2在骨骼和结缔组织祖细胞亚群中表达，但在成肌细胞中不表达。这两个基因在牙间充质中均未表达，在经历广泛生长和形态发生的腭突口腔侧也未表达。我们首次证明了Foxp1和Foxp2在颅面发育过程中表达。我们的数据表明，Foxp基因可能调控颌的口外和后部区域的发育。
