Morphogenetic Cell Movements Flashcards
(20 cards)
What is invagination?
Inward folding of a sheet of cells (e.g. primitive streak)
What is ingression?
Individual cells migrate inward as mesenchyme
What is epiboly?
Spreading and thinning of ectodermal sheets
What is convergent extension?
Cells intercalate to elongate and narrow tissues
What is delamination?
One sheet of cells splits into two layers
What is migration?
Movement of individual cells through ECM
Which movement forms the primitive streak?
Invagination + convergent extension
Which germ layers form by ingression?
Mesoderm and definitive endoderm
What initiates EMT during ingression?
Loss of E-catherin and apical-basal polarity
What structure undergoes epiboly?
Ectoderm
Which movement drives notochord elongation?
Convergent extension
Which signalling pathway drives convergent extension?
Wnt/PCP (planar cell polarity) pathway
Which genes are part of the PCP pathway?
Dishevelled, Vangl, Celsr
What guides mesodermal migration?
FGF, Wnt, and ECM interactions
Where do cells ingress during gastrulation?
Through the primitive streak
What is the role of fibronectin in migration?
An ECM protein guiding mesoderm migration
Which model organism is used to study cell movement?
Chick, frog (Xenopus), zebrafish
What is apical constriction?
Actin-mediated narrowing of apical surfaces during invagination
What movement helps form the neural tube?
Convergent extension + invagination
Which cell movement forms the hypoblast?
Delamination (in some species)
