1 Flashcards
Cell communications
- electrical and metabolic
- endocrine
- paracrine
- autocrine
- juxtacrine
Cells communicate via?
GAP junctions
GAP junctions are composed of?
composed of connexin proteins that make up two connexons
** allow passage from 1200Da
how many Da is one amino acid?
110 Da
Charcot Marie- tooth Disease has mutations in which gene?
- in the CJB1 genes encoding connexin 32
- leads to progressive loss of myelin and degradation of peripheral nerves
what is a zymogen ?
an inactive substance which is converted into an enzyme when activated by another enzyme.
(enzyme precursor)
what is a pro-drug?
Prodrugs are designed to be inactive when first administered and then become active when metabolized
what kind of signaling is long distance and acts in tissues throughout the body?
endocrine (hormonal)
paracrine signalling
- occurs b/w two adjacent cell
- i.e. Neurotransmitters
there is a secretory cells (releasing a signal molecule)
and a target cell (with the receptors)
Autocrine Signalling
self signalling
- one cell secretes signal and responds to it
- e.g. Wnt, GF, vitamins
Hydrophobic signals do what?
can readily cross the PM
can enter the nucleus and alter gene expression
Graves Disease is what?
- an autoimmune disease
- too much thyroxine (T4)
- hyperthyroidism
characteristics of the RARE
- 6bp DIRECT repeat separated by 5 nucleotides
what is a teratogen?
Teratogens can affect the fetus in various ways, including cell death, altered cell interactions, or changes in cell movement during development.
(I.e. Retinoids)
what is Cyp26A1 and what does it do?
- it is a cytochrome p450 member
- inactivates RA signaling (add an -OH group )
ERE (estrogen response elements) have what kind of repeats?
- inverted
what is a DNA adduct?
A DNA adduct is a piece of DNA that has been covalently bonded to a chemical, often a carcinogen
Response elements in
graves disease?
TR and RXR
cytochrome p450 is present in most —– of cells ?
Endoplasmic Reticulum
(abundant in liver)
what is cisplatin?
Cisplatin is a type of chemotherapy drug. It contains the metal platinum, which binds to and damages the cell’s DNA, preventing it from being repaired or copied (adduct)
Cytochrome p450 is what kind of protein?
- moonlighting protein, as it has many unrelated functions within cells
