increasing levels of cardiolipin differentially influence packing Flashcards
cardiolipin is predominately localized where
inner mitochondrial membrane
Some (4) roles of CL
directly binding ETC proteins, releasting cytC in apoptosis, facilitating leakage of protons, regulating mitochondrial structure
Changes in cardiolipin associated with pathologies
peroxidation, mass, acyl chain composition
In type 1 diabetic heart levels of tetralinoleoyl CL decrease at the expense of ?
increasing levels of long chain polyunsaturated fatty acids
Many pathologies show decreased CL mass or remodeling driven by ?
reduced CL biosynthesis and increased CL degradation
CL’s structural role is driven by its unique __ shape which is a result of four acyl chains with a relatively small headgroup
cone
CL has a propensity to form ___ ___ phase in synthetic bilayers, particularly in the presence of divalent cations which is relevant for membrane fusion and curvature and mitochondrial function
inverted hexagonal
earlier studies showed that CL served to increase/decrease the area per molecule when interacting with other phospholipids as calculated by percent condensation and elastic compressibility of monolayers on the air-water interface
decrease
electron spin resonance studies revealed that CL stabilized/destabilized the bilayer by increasing/decreasing fluidity
electron spin resonance studies revealed that CL stabilized the bilayer by decreasing fluidity
fluorescence correlation spectroscopy showed CL increased/decreased fluidity of supported bilayers made of phosphatidylcholine
increased
four major phospholipids incorporated
PC, PE, PS, PI
large unilammelar vesicles characterized as loose, intermediate or tightly packed based on ?
peak fluorescence of intensity of merocyanine (MC540)
Effect of CL on large unilammelar vesicles packing
generally decreases packing but in select cases either doesn’t change or increases packing
difference between DOPC and PDPC and DPPC
??
Each batch of CL was verified using ?
gas chromatography
All vesicles were made above/below the phase transition temperature of the lowest/highest melting phospholipid to prevent oxidation
above the highest
CL caused ? in tightly packed LUVs
dose dependent decrease in packing
CL caused ? in loosely packed LUVs
dose dependent increase in packing
CL caused ? in intermediate packed LUVs
non dose dependent. either no effect or decreased packing
sizes of homogenous LUVs
?
can we make CL vesicles?
?
physiological PC:PE:PS:PI ratio
40:30:6:4 w/w
increasing the levels of membrane polyunsaturation generally increases/decreases membrane packing due to increased conformational flexibility
decreases
Result of adding CL to most physiologically relevant LUV
dose dependent increase in fluorescence intensity, decrease in packing
CL effectively/uneffectively condenses with PC
effectively
