Week 6 - Epigenetics Flashcards
3 common mechanisms that affect gene expression
positive feedback loops
inheritance of DNA methylation patterns
inheritance of chromatin states
a positive feedback loop can generate a long-lived change in _____ _______ in response to a ______ signal
gene expression, transient signal
methylation of ______ bases in DNA can _____ transcription
cytosine, repress
master regulatory switch gene for muscle
MyoD
DNA methylation patters can be ______
inherited
_______ nucleosomes are the basic units of choromosome structure
nucleosomes
a patter of modification of ______ tails can regulate transcription
histone
can histone tail modification patters be inherited
yes
______ ________ ________ can reposition nucleosomes and control transcription
chromatin remodeling complexes
euchromatin
extended chromatin structures, promote transcription
heterochromatin
condensed chromatin structures, little or not transcription
extended chromatin structures
euchromatin
condensed chromatin structures
heterchromatin
in females, one of the ____ chromosomes is packed into _______ to prevent a lethal double -dose of _____ linked products
X , heterochromatin, X
females are have ___ X chromosomes and ____ Y chromosome
2 0
males have ___ X chromosomes and ___ Y chromosomes
1, 1
what is the key difference between worker and queen bees?
diet. Queen gets royal jelly, which does not contain chemicals that differentiate the workers
localization of a cell fate determinant in yeast involves ____ particles, a _____ and the ____ _______
RNP, motor, actin cytoskeleton
in budding yeast, _____ initiates a mating type switch
HO
in budding yeast, ______ inhibits transcription of _____ in ________ cells, preventing mating type switch
Ash1 , HO, daughter
asymmetric localization of ASH1 requires the ______
cytoskeleton
what would happen if you inhibited F-actin in yeast?
ASH1 would not aggregate on one side, and would inhibit all HO, so no more mate type swithing
what is an oocyte?
a cell in an ovary that may undergo meiotic division to form an ovum.
first major event of embryogenesis
fertilization
second major event of embryogenesis
cleavage
third major event of embryogenesis
gastrulation
3 layers of the embryo
endoderm, mesoderm, ectoderm
ectoderm makes:
skin, brain
endoderm makes:
liver, pancreas
mesoderm makes
muscle
gastrulation begins with the formation of the ____+ ____
ventral furrow
