Parrilla Marta, Chang Isabelle, Degl'Innocenti Andrea, Omura Masayo
Max Planck Institut für Biophysik, Frankfurt am Main, Germany.
Unità di Biologia Cellulare e dello Sviluppo, Dipartimento di Biologia, Università di Pisa, Pisa, Italy.
J Comp Neurol. 2016 Oct 1;524(14):2713-39. doi: 10.1002/cne.24051. Epub 2016 Jun 19.
Homeobox genes constitute a large family of genes widely studied because of their role in the establishment of the body pattern. However, they are also involved in many other events during development and adulthood. The main olfactory epithelium (MOE) is an excellent model to study neurogenesis in the adult nervous system. Analyses of homeobox genes during development show that some of these genes are involved in the formation and establishment of cell diversity in the MOE. Moreover, the mechanisms of expression of odorant receptors (ORs) constitute one of the biggest enigmas in the field. Analyses of OR promoters revealed the presence of homeodomain binding sites in their sequences. Here we characterize the expression patterns of a set of 49 homeobox genes in the MOE with in situ hybridization. We found that seven of them (Dlx3, Dlx5, Dlx6, Msx1, Meis1, Isl1, and Pitx1) are zonally expressed. The homeobox gene Emx1 is expressed in three guanylate cyclase(+) populations, two located in the MOE and the third one in an olfactory subsystem known as Grüneberg ganglion located at the entrance of the nasal cavity. The homeobox gene Tshz1 is expressed in a unique patchy pattern across the MOE. Our findings provide new insights to guide functional studies that aim to understand the complexity of transcription factor expression and gene regulation in the MOE. J. Comp. Neurol. 524:2713-2739, 2016. © 2016 Wiley Periodicals, Inc.
同源框基因构成了一个被广泛研究的基因大家族，因为它们在身体模式的建立中发挥作用。然而，它们在发育和成年期的许多其他事件中也发挥着作用。主嗅觉上皮（MOE）是研究成年神经系统神经发生的一个优秀模型。对发育过程中同源框基因的分析表明，其中一些基因参与了MOE中细胞多样性的形成和建立。此外，气味受体（ORs）的表达机制是该领域最大的谜团之一。对OR启动子的分析揭示了其序列中存在同源结构域结合位点。在这里，我们通过原位杂交来表征一组49个同源框基因在MOE中的表达模式。我们发现其中7个基因（Dlx3、Dlx5、Dlx6、Msx1、Meis1、Isl1和Pitx1）呈区域表达。同源框基因Emx1在三个鸟苷酸环化酶阳性群体中表达，其中两个位于MOE，第三个位于鼻腔入口处一个称为格林内伯格神经节的嗅觉子系统中。同源框基因Tshz1在整个MOE中以独特的斑片状模式表达。我们的研究结果为指导旨在了解MOE中转录因子表达和基因调控复杂性的功能研究提供了新的见解。《比较神经学杂志》524:2713 - 2739，2016年。©2016威利期刊公司。
