Introduction to Developmental Biology Flashcards
What is development?
A change in structure over time
Define embryogenesis
Development of an embryo from the fertilised egg
Define regional specification
Pattern formation. How pattern appears in a previously similar population of cells
What does regional specification involve?
Laying down the whole body plan and defining the main body axes
Define morphogenesis
The shaping of organs and tissue in 3D
What does morphogenesis require?
Cell and tissue movement
What are model organisms used for?
- Identifying genes with roles in developmental processes
- Understand gene function
- Provide models for human disease
What organisms are used for experimental embryology?
- Frog
- Chick
Advantages of using a frog for experimental embryology
- Big embryo
- Obvious poles
- Lots of offspring
- Easy to fertilise
Disadvantages of using a frog for experimental embryology
- Long development
- Not all thrive
- Yolky embryo
Give examples of experiments that frogs are used for
- Tissue transplantations
- Microinjection
- Transgenesis
Advantages of using a chick for experimental embryology
- Embryo outside body –> good for manipulation
- Chimeras
- Big embryo
Disdvantages of using a chick for experimental embryology
- Not accessible early
- Genetic analysis difficult
Give examples of experiments that chicks are used for
- Tissue transplantation and culture
- Retrovirus injection
- Electroporation
What organisms are used for studying developmental genetics?
- Zebrafish
- C. elegans
- Drosophila
- Mouse
Advantages of using a zebrafish for developmental genetics
- Transparent
- Short life cycle
- Lots of embryos
- Small vertebrate
- Haploid development possible
Disdvantages of using a zebrafish for developmental genetics
- Large genome
Advantages of using mice for developmental genetics
- Knockout models of human disease
- Mammals
- Easy to keep
Disdvantages of using mice for developmental genetics
- Poor accessibility
- Expensive
- Small batches of embryo
Give examples of experiments that mice are used in
- Knockout
- Microinjection
Advantages of using a fly for developmental genetics
- Large batch
- Quick development
- Human homologues
- Small organism
Disadvantages of using a fly for developmental genetics
- Small embryo
Give examples of experiments that Drosophila are used in
- Transgenesis
- Mutagenesis
Advantages of using a worm for developmental genetics
- Every cell is mapped
- Hermaphroditic
- Constantly reproducing
Disadvantages of using a worm for developmental genetics
- Small embryo
Give examples of experiments that C. elegans are used in
- Mutagenesis
- RNA interference
What is aniridia?
Absence of the iris
What causes aniridia?
Single copy mutation in the PAX6 gene
What does a mutation in both copies of PAX6 lead to?
Absence of eyes and a defect in the craniofacial structure –> don’t survive
What does PAX6 code for?
A member of the paired box class of transcription factors
What is PAX6 required for?
The development of the eye
Is PAX6 sufficient?
Yes
Is PAX6 necessary?
Yes
If anchor cells are removed in C. elegans….
No vulva is formed
