Concept explainers
(a)
To determine: The results expected if the inside-out vesicles are subjected to the GO/3H-BH4 procedure.
Introduction: Erythrocyte membranes can be used to prepare sealed vesicles. These vesicles are prepared such that their orientation is reverse. This means that the side of the erythrocyte membrane which faced the cytoplasm, face outwards in these vesicles.
(b)
To determine: The results expected if the inside-out vesicles are subjected to the LP/125I procedure.
Introduction: Erythrocyte membranes can be used to prepare sealed vesicles. These vesicles are prepared such that their orientation is reverse. This means that the side of the erythrocyte membrane which faced the cytoplasm, face outwards in these vesicles.
(c)
To determine: The conclusions that can be drawn if some of the proteins that become labeled by the LP/125I method of part (b) were among those that had been labeled when intact cells were treated such that they were incubated with LP in the presence of 125I and the membrane proteins were extracted and analyzed on SDS-polyacrylamide gels.
Introduction: Erythrocyte membranes can be used to prepare sealed vesicles. These vesicles are prepared such that their orientation is reverse. This means that the side of the erythrocyte membrane which faced the cytoplasm, face outwards in these vesicles.
(d)
To determine: A method by which a transmembrane protein can be labeled such that it has 3H on one side and 125I on the other side.
Introduction: Erythrocyte membranes can be used to prepare sealed vesicles. These vesicles are prepared such that their orientation is reversed. This means that the side of the erythrocyte membrane which faced the cytoplasm, face outwards in these vesicles.
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Becker's World of the Cell (9th Edition)
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