Stem Cells Flashcards
Self-renewal
Ability to duplicate and maintain 100% identity in a daughter cell
Developmental hierarchy
Totipotent –> Pluripotent –> Multipotent
Stem cells come from founder cells
Transit amplifying cells are programmed to divide for a limited number of times (defect in this results in cancer)
We can monitor and track the genome of stem cells
Using labels
Stem cells can selectively retain original DNA
Used to prevent genetic errors, daughter stem cell would retain original stem cell characteristics
Second cell gets newly synthesized strand
Immortal strand hypothesis
Stem cells can divide but the pure original stem cell will always be conserved. New cells can become transit amplifying (committed cells)
Types of Stem Cells
- Embryonic Stem Cells
- Adult Stem Cells, Tissue Specific Stem Cells
- Induced Pluripotent Stem Cells (iPS cells)
Stem cells need proper environmental cues to develop correctly
Embryonic stem cells come from blastocyst
Embryonic stem cells can develop into disorganized growths called teratomas
Seen when developing ES cells in vitro
4 gene regulatory proteins
OCT3/4, SOX2, MYC and KIF4
Transcription factors to know
NANOG, OCT4, SOX2
Bone marrow derived stem cells = stromal cells
Can give rise to supportive structures like connective tissue
Bone marrow cells can become hematopoeitic
Develop into any blood cell product
Inherent capability in the cell to regenerate brain cells
Adult stem cells can regenerate neuronal cells in the brain
Mesenchymal cells of bone marrow have a lot of potential
Very hard to get iPS to become pluripotent, usually multipotent
