Bober E, Baum C, Braun T, Arnold H H
Department of Cell and Molecular Biology, Technical University of Braunschweig, Federal Republic of Germany.
Dev Biol. 1994 Mar;162(1):288-303. doi: 10.1006/dbio.1994.1086.
We have identified three novel mouse homeobox genes that are related to the Drosophila NK gene family. Two genes without direct homologues in Drosophila were designated Nkx-5.1 and Nkx-5.2; the third gene Nkx-1.1 constitutes the mouse homologue to NK1.Nkx-5.1 and Nkx-5.2 are closely linked on mouse chromosome 7, whereas Nkx-1.1 is located on a different chromosome. Here, we report the spatiotemporal expression pattern of Nkx-5.1 during prenatal mouse development. Nkx-5.1 gene activity begins at Embryonic Day 10.5 in the developing ear, the neural tube, and dorsal root ganglia. It continues to be active throughout prenatal life in discrete regions of the brain with an anterior border in the ventral diencephalon at the optic chiasma and expression domains in mesencephalon, metencephalon, and myelencephalon. At midgestation, Nkx-5.1 is also expressed in mesenchyme of the head and branchial arches, and in some cranial ganglia, as well as in derivatives of neural crest, such as the truncus sympathicus and myenteric ganglia. The time pattern of Nkx-5.1 expression and its confinement to primarily postmitotic cells of the central and peripheral nervous system suggest that Nkx-5.1 may play a role in the specification of neuronal cell types.
我们已经鉴定出三个与果蝇NK基因家族相关的新型小鼠同源异型盒基因。在果蝇中没有直接同源物的两个基因被命名为Nkx-5.1和Nkx-5.2；第三个基因Nkx-1.1构成了小鼠中与NK1同源的基因。Nkx-5.1和Nkx-5.2在小鼠7号染色体上紧密连锁，而Nkx-1.1位于不同的染色体上。在此，我们报道了Nkx-5.1在小鼠产前发育过程中的时空表达模式。Nkx-5.1基因活性在胚胎第10.5天开始于发育中的耳朵、神经管和背根神经节。在整个产前生命过程中，它在大脑的离散区域持续活跃，在前脑腹侧视交叉处有一个前缘，在中脑、后脑和延髓有表达区域。在妊娠中期，Nkx-5.1也在头部和鳃弓的间充质、一些颅神经节以及神经嵴的衍生物中表达，如交感干和肠肌神经节。Nkx-5.1表达的时间模式及其主要局限于中枢和外周神经系统的有丝分裂后细胞表明，Nkx-5.1可能在神经元细胞类型的特化中发挥作用。
