Gene Expression in Development Flashcards
what are totipotent cells?
- e.g cells of the very early mammalian embryo
- identical and unrestricted
- can give rise to any cell of body
- embryonic
what are pluripotent cells?
- e.g inner cells of the blastocyst
- less potent
- can give rise to many cell types but not all
- embryonic
what are multipotent cells?
- e.g. blood cells
- can give rise to cells that have a particular function
- adult
what are the two stages of cell commitment?
- specification - reversible
2. determination - itteversible
what are features of specification stage?
capable of differentiating autonomously if placed in isolation BUT can be respecified if exposed to certain chemicals/signals
what are features of determination stage?
cell will differentiate autonomously even when exposed to other factors or placed in a different part of the embryo
what is cell fate?
what it will become in the course of normal development:
- when a cell “chooses” a particular fate it is said to be determined
- still looks like its undetermined neighbours
- determination implies stable change, fate of determined cells does not change
what is competence of a cell?
ability of a cell to respond to the chemical stimuli - a cell can lose competence by changes in surface receptor or intracellular molecules
how does a naive cell become specified?
by intrinsic or extrinsic signal:
intrinsic: (cytoplasmic determinant) - cell autonomous signal tells cell ‘who it is’
extrinsic: (induction) - a chemical or molecule in the environment gives cell spatial info, tells cell ‘where it is’
what is brainbow technology?
- tracks neuronal development and cell fate
- cells tracked over time
- stochastic colour expression in neuronal cells