Vertebrate eye gene regulatory networks

Abstract

The development of the eye in vertebrates entails the precise coordination of the genetic programs that control morphogenetic movements and inductive signals. The basic blueprint of the vertebrate eye is established in the developmental window comprised between the specification of the eye field at early gastrulation and the onset of neuronal differentiation (Martinez-Morales and Wittbrodt in Curr Opin Genet Dev 19(5):511-517, 2009; Fuhrmann in Curr Top Dev Biol 93:61-84, 2010; Sinn and Wittbrodt in Mech Dev 130(6-8):347-358, 2013). During this period, the precursor cells from the eye primordium get specified, and then differentiate to form three major tissue domains: the neural retina, the retinal-pigmented epithelium (RPE), and the optic stalk domains. A process that culminates with the formation of the optic cup, a highly conserved embryonic structure that represents a common arrangement for the embryonic eye in vertebrates (Tena et al. in Genome Res, 2014). This chapter will focus in the architecture of the Gene Regulatory Networks (GRNs) during early organogenesis. The structure of the GRNs involved in the initial specification and differentiation of the major non-neural component of the eye, the lens, will not be examined here. The reader is referred to the following reviews for a detailed discussion on this subject (Cvekl and Duncan in Prog Retin Eye Res 26(6): 555-597, 2007; Cvekl and Ashery-Padan in Development 141(23):4432-4447, 2014).