ACB 406.3 Lecture Notes - Lecture 18: Pineal Gland, Lamellar Granule, Tunicate

• School: U of S
• Department: Anatomy and Cell Biology
• Course: ACB 406.3
• Professor: Helen Nichol

Document Summary

Lower animal retinas fish and birds have the same 10 layers as mammals. The common ancestor of cnidarian, protostomes and deuterostomes already possessed the great majority of the components needed for constructing an ocellus and/or a retina. E. g. it already possessed transcription factors, growth factors, opsins, photoreceptor cells, the ciliar and microvillar forms, pigment cells, neurons and etc. The genes were already present in the lower vertebrates. Light-sensitive organs (frontal eye) in the head region of the larval amphioxus: the frontal eye and lamellar bodies contain ciliary cells, dorsal ocelli = eye spot in the dorsal side of the animal. Molecular fingerprint of the frontal eye of larval amphioxus: the expression profile of vertebrate eye-specific regulatory genes (rx, otc, Pax4/6, mitf) and eye-associated proteins (c-opsins, gi melanin) supports the homology of row 1 cells (green) w/ vertebrate photoreceptors, and of pigment cells (blue) w/ vertebrate rpe cells.