Plasma membrane Flashcards
What is the charge of plasma membrane and who gives it?
Negative
Polar head are negative and fatty chain is uncharged
Three types of lipid bilayer
Phospholipid, glycolipid and sterols
What is lecithin?
Phosphotidylcholine
What are the negative glycerophospholipid?
Phosphotidylserine and phosphotidylinositol
Three types of glycolipid
Cerebroside, globoside and ganglioside
What are lipid rafts
Domain having cholesterol and sphingolipids
Two types of lipid rafts and their protein
Planar and caveolae.
Protein of planar is flotilin
Protein of caveolae is caveolin
Function of lipid rafts
Cholesterol trafficking, signal transduction, endocytosis.
Ionophores
They are small lipid molecules that are soluble in lipid and increases the permeability of specific inorganic solutes
Eg. of ionophores
Valinomycin, monensin and gramicidin A
What does Valinomycin, gramicidin and monensin does?
Valinomycin: transports k+ ions
Monensin : transport Na+ ions
Gramicidin A: transports water and univalent cations
How many aquaporins does human have? Which one is present on the epithelium of renal duct
10 isoforms and AQP2 is present on renal duct
Two hydrophobic domain of aquaporins consist of?
Asparagine, proline and alanine
N and C terminal of Aquaporins are in which side?
Cytosolic
Na+ K+ ATPase has how many subunits
Three a,b and r
Inhibitors of na-k ATPase
Oubain, digoxin, palytoxin and cardiotonic steroids
Hydropathy plot
The plot that determines the hydrophobic amino acid in a protein
P Type ATPase
Cation transporters that undergo reversible phosphorylation of a conserved aspartate residue
Eg. Of P type ATPase
Na-K ATPase, H-ATPase and Ca2+ ATPase
V Type ATPase
Transport protons.
Present in the vacuolar membrane, endosomal membrane and lysosomal membrane.
F Type ATPase
Transports only protons.
Doesn’t involve phosphorylation
Where is F Type ATPase found in eukaryotes.
Inner mitochondrial membrane
Where is F type ATPase found in plants
One in mitochondria and another in thylakoids
What does ABC transporters transport?
Ions, sugar, amino acids
Where are ABC transporters found?
In plasma membrane, ER, mitochondria and lysosome.
Name the two domains of ABC transporter
Transmembrane domain and nucleotide binding domain
Give an example of ABC transporter and its function.
P Glycoprotein
It’s multidrug resistant. Especially in lung cancer cells.
CFTR
Cystic fibrosis transmembrane conductance regulator.
A type of ABC transporter.
Where is CFTR found?
In lungs, gastrointestinal tract, liver, pancreas, sweat gland, and reproductive tract.
What does CFTR protein transport?
Chloride ions out of the cell.
What happens if the CFTR is defective?
Cystic fibrosis
Give an example of a secondary active transporter.
Na-glucose transporter and lactose permease (H - galactoside symporter)
