genes & development Flashcards
during embryogenesis 2 things happen -
- organism gets bigger (proliferation)
- organism gets more complex (differentiation)
cell differentiation is controlled through
regulation and programming, and through cell-signalling
cells have same genotype but different phenotype - how
different cells express different genes, which code for proteins
staining technique to show cells with active gene
in situ hybridisation - blue colour
each gene has a specific ….. of stained cells in the embryo, what colour shows cells which express the gene
expression pattern, blue colour
gene required for limb development
FGF10
fertilisation –> cleavage (rounds of division) –> blastula (hollowed embryo) –> ….
gastrulation (germ layer formation)
endoderm gives rise to
lungs, stomach, liver, intestine
mesoderm gives rise to
notochord, somites, kidney, bones, muscle, heart, gut
ectoderm gives rise to
brain, spinal cord, autonomic NS, skin, melanocytes, skull
…… can be used to study development
model organisms
regulator of eye development (transcription factor) is controlled by …. gene
Pax6
requirement of Pax6 was found to be
conserved across species (invertebrates)
the fertilised egg is called the
zygote
neural plate gives rise to
brain and spinal cord
neural crest gives rise to
autonomic system
skull
melanocytes
experimental approach of pax6 gene
pax6 RNA from 16 cell stage
-incubate for 72 hours
formation of tadpole
ectopic pax 6 induces
eye markers
xenopus loss/gain of function
extra eyes/lack of eyes
Pax6 in vertebrates required for
human eye development
