Differentiation Flashcards
When is gene expression regulated
transcriptionally, post-transcriptionally, translationally & post-translation
What are the types of gene expression regulation post-transcription
RNA splicing, nuclear transport
What regulates transcription
promoter and enhancer sequences, transcription factors
What does transcription factor activity depend on
extrinsic & intrinsic factors, regulatory binding sites, accessibility of chromatin
What can somites become
skeletal muscle, dermatome, myotome, and sclerotome
What do dermatomes become
dermis
What does the myotome become
skeletal muscle
What does the sclerotome become
vertebrae and ribs
What do mesodermal progenitors give rise to
myoblasts
what do myoblasts give rise to
multi-nucleate myotube
what do multi-nucleate myotubes give rise to
muscle fibres
describe the determination of mesodermal progenitors
uncommitted
TRUE or FALSE - myoblasts express muscle specific proteins
FALSE
Which type of cell in skeletal muscle development express muscle specific proteins
multi-nucleate myotubes
What are the muscle specific proteins
muscle specific actin, myosin II, tropomyosin, muscle specific enzymes
What is MyoD
transcription factor
Where is MyoD expressed
early on in muscle precursors
What does MyoD control
expression of genes for muscle differentiation
How is MyoD maintained
maintains own expression - in a positive feedback loop
TRUE or FALSE - fibroblasts express MyoD
False
TRUE or FALSE - MyoD is sufficient to direct muscle cell fate
TRUE
What happens to muscle development in mice if they lack MyoD
skeletal muscle develops normally
What happens to muscle development in mice if they lack MyoD and Myf5
lack ALL skeletal muscle
Where do stem cells lie in human epidermis
basal layer
What cells lie in the human epidermis
stratified epithelium
What separates the epidermis from the dermis
basal lamina
What adult stem cells are present in skeletal muscle
satellite cells
what is the function of satellite cells
proliferate and differentiate if muscle is damaged
Where do satellite cells lie
between basal lamina and cell membrane of mature muscle fibres
What do satellite cells in skeletal muscle express
specific marker proteins
What is apoptosis used for in development
inter-digit cells in limbs, neurons in CNS
Why do differentiated tissues retain some stem cells
cell renewal and repair
