Exam 3 Flashcards
Substrate-Level Phosphorylation vs Proton Motive Force ATP Production
SLP: in cytoplasm (glycolysis) and mitochondrial matrix (Krebs cycle). absence of oxygen.
PMF: occurs in membranes of chloroplasts and mitochondria. Starts with light or nutrients, respectively.
Mitochondria-Associated Membranes (MAMs)
Specialized regions of the ER that directly contact mitochondria and influence mitochondrial shape, function, and sites of fission.
Locations of Krebs Cycle and ETC
K: Mitochondrial matrix.
ETC: inner mitochondrial membrane.
Products of Krebs Cycle
NADH
GTP
FADH2 (carries electrons to complex II)
CO2
Allosteric downregulation of cellular respiration
Excess ATP allosterically interacts with and downregulates the conversion of Fructose 6 phosphate to Fructose 1,6 bisphosphate via phosphofructokinase.
Redox Potential
Tendency of acquiring electrons.
More positive = greater affinity.
Flow of Electrons in ETC from NADH and FADH2
N: Complex I, Complex III, Complex IV
F: Complex II, Complex III, Complex IV
Pulse Chase Experiment
Used radioactive P54 to find that secretory proteins are located in the ER lumen directly after synthesis.
SRP
Directs proteins into organelles. Translocon on organelle membranes allows entrance.
Location of post-translational modifications
Rough ER
ERAD
ER Associated Degradation.
Misfolded proteins are tagged by ubiquitin, transported into the cytoplasm, and degraded by proteasomes.
ER Resident Chaperone Proteins:
PDI
Bip
Calnexin/Calreticulin
Oligosaccharide Transferase
PDI: oxidized form forms disulfide bonds and corrects improperly folded disulfide bonds.
Bip: prevents premature folding.
C/C: assist in folding process.
OT: transfer OSs from FAs to proteins; attaches them to Asparagine on peptide chains.
Type I, II, and IV integral proteins
Type I: N Terminal in either ER lumen or outside of cell.
Type II: N Terminal in cytosol. No ER signal or signal anchor sequence.
Type IV: multiple passes.
COP II
ER to cis Golgi (anterograde).
2 coats: Sec 23/24 and Sec 13/31.
COP I
Cis Golgi to ER (retrograde).
Coat has 7 components.
Clathrin
Trans Golgi or Plasma Membrane to endosome or lysosome.
TG: AP1 and Clathrin.
PM: AP2 and Clathrin.
Vesicle Fusion
SNARE Complex
Disassembly mediated by NSF and ATP hydrolysis.
KDEL/KKXX
Signals for retrograde traffic for escaped ER resident proteins to return to ER.
Processes carried out in Cis, Medial, and Trans Golgi
Cis: Mannose trimming (mannosidase).
Medial: hyperacetylation in glucose derivatives, addition of fucose.
Trans: addition of galactose.
Movement of cargo in Golgi
Anterograde: cis maturation.
Retrograde: COP I.
Mannose-6-Phosphate
Directs proteins to endosome/lysosome.
Phosphorylation of Mannose occurs in Golgi.
Endocrine
Paracrine
Autocrine
Membrane Proteins
E: long range via bloodstream; insulin.
P: secretory cells; short range via diffusion; NTs, GFs.
A: own cell; short range via diffusion; tumor cells.
MP: adjacent cells; no travel required; during development.
Protein Kinases
Phosphatases
Kinase: causes phosphorylation.
Phosphatase: causes dephosphorylation.
IP and AP
IP: agonist of Epi.
AP: antagonist of Epi.
GPCR-IP3 Pathway
Involves Calcium
Produces nitrous oxide gas that relaxes smooth muscle and reduces BP.
TGF-Beta and SKI
TGF-B: tumor suppressor; increases production of ECM.
SKI: oncogenic; antagonist of SMAD; shuts down TGF-B and SMAD along with HDAC and causes cancerous cells.
Hyperactivity of EpoR, JAK, or STAT can cause…
Cancer of blood or other.
Can utilize knock out/down tech for anti-cancer therapies.
Regulation of FGFR
Proteoglycan mediates complex between FGFs and FGFRs.
