Final extra material Flashcards
Wnt (Wnt/beta-catenin) signaling pathway
fig 3.16
What are antagonists of paracrine factors?
secreted molecules that block the action of paracrine factors
What is involved in the downregulation of BMP?
- Noggin
- Chordin
What is Direct Cell Contact?
Contact between the inducing and responding cells
What does the delta-notch pathway do?
controls multiple cell differentiation processes during embryonic and adult life and is dysregulated in many cancers
Where do you see the delta noch pathway?
- Gliogenesis
- Left-reight asymmetry determination
- Somite Formation
What is the function of Lunatic Fringe?
- Acts in the Golgi to modify Notch and alter the ability of Notch to bind its ligand Delta
- Establishes the anterior boundary of somites
How is the extracellular matrix involved in cell communication?
The matrix of one cell induces change in another cell
What are Integrin?
- The principal receptors used by animal cells to bind to the extracellular matrix
- Heterodimers
- Function as transmembrane linkers between the extracellular matrix and the actin cytoskeleton
What are some signaling pathway examples?
- Branch points for multiple responses
- Crosstalk; integration of multiple signals
- Reciprocal communication/induction
How do cells become committed to forming a particular tissue?
Cells receive signals that cause them to develop down a certain pathway
Cell Fate is…
What a cell or tissue will develop into during the development
When a cell first becomes committed to a particular fate, it does not appear phenotypically different from its uncommitted state.
Having a particular normal fate does not imply that a cell could not develop differently if placed in a different environment
Potency is…
What a cell or tissue could become during development if it were allowed to develop in another envirinent
What is cell commitment?
The state in which a cell’s developmental fate has become restricted even though it is not yet displaying overt changes in cellular biochemistry and function
Cell Specification…
Occurs when a group of cells gain a bias toward certain fate (the normal fate) and if isolated and cultures in a neutral medium they develop according to normal cell fate
Determination is when…
Cell fate becomes irreversible: a stable change in the internal state of a cell occurs such that its fate is now fixed, or determined.
A determined cell can not longer develop in accordance with new environment signals
What is induction?
Instructive signals from one cell or tissue that cause a change in the cellular behavior of adjacent responding cells
What is competence?
Cells in the presence of the signal must be competent to respond for a change to occur
What are two ways cells can be differentially induced?
- Morphogen Gradients
- Lateral Inhibition
Morphogen Gradients
Cells respond to signals in a concentration-dependent manner
What are morphogens used for?
To give positional information
What are morphogens?
signaling molecules that emanate from a restricted region of tissue and spread away from their source to form a concentration gradient.
What are morphogen gradients used for?
they are used for spatial regulation of gene expression
Morphogen-concentration-dependent induction of….
gene expression