Exam 4 Part 3 Flashcards
Bcl2 gene
activated/upregulated by survival factor
product inhibits Bax/Bak
Ways to measure apoptosis
DNA laddering Cleaved caspase 3 TUNEL stain Phosphatidylserine exposure on extracellular side membrane blebbing vacuole formation
DNA laddering
chopped up DNA that occurs during apoptosis. Can be visualized by electrophoresis and looking at DNA six
mostly for cell cultures
cleaved caspase 3
indicates apoptosis
can use a Western blot and probe with antibodies to compare between number of procaspases and caspases
TUNEL stain
Terminal dUPT nick end labeling
immunocytometry to look for cut DNA and have a fluorescent mark for where DNA is cleaved
PHosphatidylserine
usually on the cytosolic side of membrane, but during apoptosis cell no longer regulates location and starts to appear at the extracellular side
use antibodies to fluores and then use flow cytometry to see if almost the whole population is going through apoptosis
membrane blebbing
cytoskeleton gets chopped up and blebs the membrane -can be see with TEM or SEM
vacuole formation
vacuoles form during apoptosis -can be seen with tEM
stem cells
precursor cells
undiferentiated or partially differentialed
generally slow dividers, can divide indefinitely
express different genes than the cells that they will make
what might signal a stem cell’s differentiation
hormones, ECM, neighboring cells, environmental stress
crypt
parts of gut that contain stem cells
stem cells will move up the villi and differentiate
multipotent stem cells
stem cells that can make a few different types of cells (ex Hemopoietic SC found in adults)
pluripotent SC
stem cells that can make any cell in your body
have unrestricted developmental potential
totipotent SC
same as pluripotent but can also make extra-embryoic tissues (placenta, etc)
obtaining embryonic stem cells
take cells of inner cell mass of fertilized embryo and put in culture
can divide forever and can generate any cell type
