Neural induction and factors that stabilize a neural fate

Abstract

The neural ectoderm of vertebrates forms when the BMP signaling pathway is suppressed. Herein we review the molecules that directly antagonize extracellular BMP and the signaling pathways that further contribute to reduce BMP activity in the neural ectoderm. Downstream of neural induction, a large number of “neural fate stabilizing” (NFS) transcription factors are expressed in the presumptive neural ectoderm, developing neural tube, and ultimately in neural stem cells. Herein we review what is known about their activities during normal development to maintain a neural fate and regulate neural differentiation. Further elucidation of how the NFS genes interact to regulate neural specification and differentiation should ultimately prove useful for regulating the expansion and differentiation of neural stem and progenitor cells.

ERF and ETV3L are retinoic acid-inducible repressors required for primary neurogenesis

“…Neural induction leads to the upregulation of Zic1, Zic3 and Foxd4l1, which allows ectodermal cells to commit to the neural fate and promotes expression of genes that maintain proliferation in the neural plate at the expense of differentiation (reviewed in Aruga and Mikoshiba, 2011;Moody and Je, 2002;Rogers et al, 2009). Erf-MO and Etv3/3l-MO embryos exhibited lateral expansion of Zic1 (Fig.…”

“…Foxd4l1 upregulates Geminin and Zic2, genes that are known to maintain the neuroectoderm in an immature proliferative state (reviewed by Moody and Je, 2002;Rogers et al, 2009). Erf and Etv3/3l MOs expanded Geminin and Zic2 expression domains (Fig.…”

“…Sox2, Sox3) are downstream of Foxd4l1, Geminin and Zic2 (reviewed by Moody and Je, 2002;Rogers et al, 2009), maintain neural progenitor cells in a proliferative state, and are downregulated during neural differentiation (Archer et al, 2011;Bylund et al, 2003;Miyagi et al, 2009;Wegner and Stolt, 2005 Fig. S6D-I).…”

“…The concerted action of these genes promotes proliferation and maintenance of immature neural precursors. Through an incompletely understood mechanism, neural progenitors of the deep neuroectoderm layer of the embryo exit from the cell cycle and differentiate into primary neurons (Chalmers et al, 2002) under the control of proneural and neurogenic transcription factors (reviewed by Rogers et al, 2009).…”

Ca2+ coding and decoding strategies for the specification of neural and renal precursor cells during development

“…Amphibian embryos and animal caps are both useful for screening the downstream target genes, which are activated by Ca 2+ signalling during neural induction [20]. In particular, it has been shown that Ca 2+ controls the expression of the immediate early gene c-fos [21] as well as that of two other transcription factors: XlPou2 and zic3 [8].…”