Membrane protein

Question 1

Paradox of membrane protein

Answer 1

Membrane protein both soluble in water and embedded in a membrane.

Different conformation in water compared to membrane

Question 2

Peripheral membrane proteins

Answer 2

Membrane protein that adhere only temporarily to the biological membrane with which they are associated

Question 3

Integral membrane proteins

Answer 3

Membrane proteins that is permanently attached to the membrane

Question 4

Rhodopsin

Answer 4

Is a light sensitive protein

Heptahelical receptors

Retinal

Question 5

Retinal

Answer 5

Light absorbing pigment, once exited goes from trans-retinal to cis-retinal

Question 6

Transmembrane β-barrels

Answer 6

Have the simplest up and down topology

Proin

K+ channel

Question 7

Signal transduction

Answer 7

Signal recognition (Extracellular domain)

Signal transmission ( Transmembrane domain)

Signal response and amplification (Intracellular domain)

Question 8

Hydropathy plot

Answer 8

Calculate the hydrophobicity from a 19aa window and plot against the aa sequence

Predict transmembrane helices from the primary structure

Question 9

Src tyrosine kinase

Answer 9

Signalprotein which controls cell growth

Signaling by phosphorylation of tyrosine

Kinase on protein is not exposed in inactive form.