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Cellular and Molecular Biology

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Endomembrane Transport: Lysosomal Trafficking

CELLS-W5TWO8

You are studying the processing of a lysosomal enzyme in the endomembrane system. When you introduce a specific point mutation in the gene sequence of the protein, the resulting enzyme accumulates in the trans cisternae of the Golgi complex and is NOT transported to the lysosome.

What is a possible cause of this?

A

The cells lack an enzyme (protein kinase) to phosphorylate mannose residues of your protein of interest.

B

A glycosylation site has been removed.

C

The protein is being recognized as misfolded by the ERAD system.

D

The mutation has created an ER retrieval tag.