The primordium of the vertebrate eye is composed of a pseudostratified and apparently homogeneous neuroepithelium, which folds inward to generate a bilayered optic cup. During these early morphogenetic events, the optic vesicle is patterned along three different axes—proximo-distal, dorso-ventral, and naso-temporal—and three major domains: the neural retina, the retinal pigment epithelium (RPE), and the optic stalk. These fundamental steps that enable the subsequent development of a functional eye, entail the precise coordination among genetic programs. These programs are driven by the interplay of signaling pathways and transcription factors, which progressively dictate how each tissue should evolve. Here, we discuss the contribution of the Hh, Wnt, FGF, and BMP signaling pathways to the early patterning of the retina. Comparative studies in different vertebrate species have shown that their morphogenetic activity is repetitively used to orchestrate the progressive specification of the eye with evolutionary conserved mechanisms that have been adapted to match the specific need of a given species.

脊椎动物眼睛的原基由假复层和看似均质的神经上皮组成，其向内折叠以产生双层视神经杯。在这些早期形态发生事件中，视泡沿着三个不同的轴（近端，背腹和鼻颞）以及三个主要区域形成图案：神经视网膜，视网膜色素上皮（RPE）和视杆。这些使功能性眼部随后发展的基本步骤需要在遗传程序之间进行精确的协调。这些程序是由信号传导途径和转录因子的相互作用驱动的，它们逐渐决定了每个组织应如何进化。在这里，我们讨论Hh，Wnt，FGF和BMP信号通路对视网膜的早期模式的贡献。