Department of Biological Sciences and Bioengineering, Indian Institute of Technology Kanpur, Kanpur, 208016, Uttar Pradesh, India; Present address: Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, USA.
Department of Biological Sciences and Bioengineering, Indian Institute of Technology Kanpur, Kanpur, 208016, Uttar Pradesh, India.
Dev Biol. 2020 Nov 1;467(1-2):95-107. doi: 10.1016/j.ydbio.2020.09.003. Epub 2020 Sep 10.
The retinotectal system has been extensively studied for investigating the mechanism(s) for topographic map formation. The optic tectum, which is composed of multiple laminae, is the major retino recipient structure in the developing avian brain. Laminar development of the tectum results from cell proliferation, differentiation and migration, coordinated in strict temporal and spatial patterns. However, the molecular mechanisms that orchestrate these complex developmental events, have not been fully elucidated. In this study, we have identified the presence of differential retinoic acid (RA) signaling along the rostro-caudal and dorsoventral axis of the tectum. We show for the first time that loss of RA signaling in the anterior optic tectum, leads to an increase in cell proliferation and gross changes in the morphology manifested as defects in lamination. Detailed analysis points to delayed migration of cells as the plausible cause for the defects in lamina formation. Thus, we conclude that in the optic tectum, RA signaling is involved in maintaining cell proliferation and in regulating the formation of the tectal laminae.
视网膜-顶盖系统已被广泛研究，以探究地形图形成的机制。视顶盖由多个层组成，是发育中鸟类大脑的主要视网膜接收结构。顶盖的层状发育是通过细胞增殖、分化和迁移来实现的，这些过程在严格的时空模式下协调进行。然而，协调这些复杂发育事件的分子机制尚未完全阐明。在这项研究中，我们已经确定了视顶盖的前后轴和背腹轴上存在差异的视黄酸（RA）信号。我们首次表明，在前视顶盖中失去 RA 信号会导致细胞增殖增加，并导致形态发生严重变化，表现为层状结构缺陷。详细的分析表明，细胞迁移延迟是导致层状结构形成缺陷的可能原因。因此，我们得出结论，在视顶盖中，RA 信号参与维持细胞增殖，并调节顶盖层的形成。
