Developmental Genetics Flashcards
What is brachyury gene required for
development of mesoderm
Brachyury is an example of which type of inheritance
incomplete dominance
What happens if an embryo is homozygous recessive for brachyury
dies
What diseases are caused by non-sense mutations
cystic fibrosis and Duchenne muscular dystrophy
What disease is caused by frameshift mutations
Tay-Sachs disease
Describe an anti-morphic mutation
dominant negative, mutant is unable to signal, acts as a competitive inhibitor
What do chemical mutagens affect
base pairing affinities
What sex is exposed to the mutagen
males
What is the function of treating organisms with mutagens
increase normal rate of mutation
What is KIT
transmembrane receptor for steel
What do kit & steel defects cause
coat pigmentation, anaemia and sterility
What is Steel
extracellular ligand
TRUE or FALSE - Kit & Steel work in the same molecular pathway
TRUE
What is the signalling of Kit & Steel required for
normal development of melanocytes, haematopoietic stem cells, and germ cells
What is the hedgehog pathway required for
normal segment pattern in drosophila embryo
What is a/the maternal genes
bicoid
What are the zygotic genes
gap, pair-role segmentation and selector
What is an example of a gap gene
hunchback
What is an example of a pair-role gene
even-skipped & fushi tarazu
What is an example of segmentation genes
wingless, hedgehog, patched, & smoothened
What is an example of selector genes
abdominal A
Describe the phenotype of a homozygous hedgehog mutant
lawn of denticles - bristles over entire surface
What other mutant is also covered in a lawn of denticles
wingless mutants
What is the function of segment polarity genes
establish formation of denticles on ventral side
What is the function of selector genes
establish identity of appendages
Describe the phenotype of a patched like mutant
excess naked cuticle - loss of denticles
What genes are required for the formation of naked cuticle
hh, smo and wg
What gene suppresses formation of naked cuticle
ptc
What expression is lost in hh & smo mutants
wingless
What expression is expanded in ptc mutants
wingless
What is hedgehog
secreted signalling molecule
What are patched & smoothened
transmembrane proteins
What is wingless
secreted signalling molecule
What is Ci
transcription factor required for wingless expression
What does hh repress
ptc
What does ptc repress
smo
What does smo activate
wg
