Department of Biology, Johns Hopkins University, Baltimore, MD, United States.
Department of Biology, Johns Hopkins University, Baltimore, MD, United States.
Vitam Horm. 2021;116:51-90. doi: 10.1016/bs.vh.2021.03.001. Epub 2021 Mar 10.
Cones are the color-detecting photoreceptors of the vertebrate eye. Cones are specialized into subtypes whose functions are determined by the expression of color-sensitive opsin proteins. Organisms differ greatly in the number and patterning of cone subtypes. Despite these differences, thyroid hormone is an important regulator of opsin expression in most vertebrates. In this chapter, we outline how the timing of thyroid hormone signaling controls cone subtype fates during retinal development. We first examine our current understanding of cone subtype specification in model organisms and then describe advances in human stem cell-derived organoid technology that identified mechanisms controlling development of the human retina.
锥体是脊椎动物眼睛中的色觉光感受器。锥体被特化为不同的亚型,其功能由对颜色敏感的视蛋白的表达决定。不同生物体的锥体亚型数量和模式差异很大。尽管存在这些差异,但甲状腺激素是大多数脊椎动物中视蛋白表达的重要调节剂。在本章中,我们概述了甲状腺激素信号的时间如何在视网膜发育过程中控制锥体亚型命运。我们首先检查我们对模型生物中锥体亚型特化的现有理解,然后描述在人类干细胞衍生类器官技术方面的进展,该技术确定了控制人类视网膜发育的机制。