Concept explainers
To review:
The expected pathway that is followed from the inside to the outside of the cell by:
a) a lysosomal enzyme,
b) a protein, which is excreted from the cell.
Introduction:
The motion of proteins is followed within a cell with the help of a pulse-chase experiment, in which the proteins are tagged during their synthesis. The tagging is done using radioactive isotope (radio-labeled amino acid), known as pulse, and the cells are monitored for protein synthesis for the certain time period.
The proteins incorporate the isotope and are labeled. Their location is then detected by isolating and separating the cell organelles and checking for radioactivity. This experiment is used to study various proteins such as protein kinases and ubiquitin.
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Life: The Science of Biology
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