13. Eye development
Overview
- Vision: solving a problem in different ways
- The adult mammalian eye
- The adult Drosophila eye
- Eye development in mammals
- Eye development in Drosophila
- Eye development: inspirational experiments
- Eye development: deciphering molecular mechanisms – PAX6
- Deciphering early eye development – from Drosophila to mammals
- Gene networks in various stages of eye development
- Implications in biomedicine
o Congenital eye defects
o Understanding teratogens
- Evolution of the eye
Goals
EXAM:
- Picture of either drosophila or mammalian eye and you have to identify the different
components. An arrow is pointing to a structure what structure is that?
- Able to identify key steps in mammalian eye development and identify what embryonic
lineages contribute to that.
Vision: solving a problem in different ways
Vision is/has been a major enabler towards evolution, and the problem has been solved in a variety
of ways. If you have no eyes, no way of perceiving light and light associated information you will
essentially be moving around more or less randomly. The moment you obtain/acquire light sensitive
cells it will allow you to move towards light or move away from it. And if on top of that you add a
reflective part that can shield part of the eye/light sensitive cells, in a way that light can only reach
the light sensitive cells from a certain direction gives you sense of direction!
If you then add more sophisticated structures such as lenses, the complexity of the image you can
acquire increases!
, In jelly fish the eyes are here, with lens! Can move
around directionally.
Squid, different eyes compared to humans (inverted
retina, light sensitive part is removed from the light
source) whereas squids and octopi have an everted
retinae, meaning that the light sensitive part is closest to
where the light comes in.
Range of solutions towards vision throughout the animal kingdom!
The adult mammalian eye
Overview of adult human eye Overview of the adult mouse eye
- Cilliary body contains small muscles that allow regulation of the diameter of the iris.
- Vitreous body, jelly like structure
- Sclera is the really hard white looking structure
- Fovea centralis place where visual acquity is the highest, small portion of the retina
responsible for very detailed vision.
Mammals have an inverted retina! Light comes from
the bottom and goes through these nuclear layers to
eventually reach the photoreceptors which is in the so
called outer segment.
OS = Outer segment contains all the light sensitive part
Rods, capture light during dim conditions
movement
Cones, capture light in bright condition colour
Light
Outer layer all about the light sensitive cells, IS
contains cell body, ONL contains nucleus, OPL
contains plexus/connecting with other neurons.
Overview
- Vision: solving a problem in different ways
- The adult mammalian eye
- The adult Drosophila eye
- Eye development in mammals
- Eye development in Drosophila
- Eye development: inspirational experiments
- Eye development: deciphering molecular mechanisms – PAX6
- Deciphering early eye development – from Drosophila to mammals
- Gene networks in various stages of eye development
- Implications in biomedicine
o Congenital eye defects
o Understanding teratogens
- Evolution of the eye
Goals
EXAM:
- Picture of either drosophila or mammalian eye and you have to identify the different
components. An arrow is pointing to a structure what structure is that?
- Able to identify key steps in mammalian eye development and identify what embryonic
lineages contribute to that.
Vision: solving a problem in different ways
Vision is/has been a major enabler towards evolution, and the problem has been solved in a variety
of ways. If you have no eyes, no way of perceiving light and light associated information you will
essentially be moving around more or less randomly. The moment you obtain/acquire light sensitive
cells it will allow you to move towards light or move away from it. And if on top of that you add a
reflective part that can shield part of the eye/light sensitive cells, in a way that light can only reach
the light sensitive cells from a certain direction gives you sense of direction!
If you then add more sophisticated structures such as lenses, the complexity of the image you can
acquire increases!
, In jelly fish the eyes are here, with lens! Can move
around directionally.
Squid, different eyes compared to humans (inverted
retina, light sensitive part is removed from the light
source) whereas squids and octopi have an everted
retinae, meaning that the light sensitive part is closest to
where the light comes in.
Range of solutions towards vision throughout the animal kingdom!
The adult mammalian eye
Overview of adult human eye Overview of the adult mouse eye
- Cilliary body contains small muscles that allow regulation of the diameter of the iris.
- Vitreous body, jelly like structure
- Sclera is the really hard white looking structure
- Fovea centralis place where visual acquity is the highest, small portion of the retina
responsible for very detailed vision.
Mammals have an inverted retina! Light comes from
the bottom and goes through these nuclear layers to
eventually reach the photoreceptors which is in the so
called outer segment.
OS = Outer segment contains all the light sensitive part
Rods, capture light during dim conditions
movement
Cones, capture light in bright condition colour
Light
Outer layer all about the light sensitive cells, IS
contains cell body, ONL contains nucleus, OPL
contains plexus/connecting with other neurons.
