Question

Select all of the examples of protein translocation across a membrane below that directly require the hydrolysis of ATP to drive the process

		movement of a protein into the mitochondrial matrix from the cytosol
		recycling of the Pex5 peroxisomal receptor to a state that will bind PTS1-containing proteins in the cytosol
		transport of NLS-containing proteins into the nucleus by importin
		co-translational translocation of proteins into the ER lumen

can be multiple answers

Answer 1

1. Mitochondrial protein import is fueled by ATP hydrolysis at two discrete sites, one outside the mitochondria and one in the matrix . In addition, another energy source is required: an electrochemical H⁺ gradient across the inner mitochondrial membrane.

2. Receptor recycling involves monoubiquitylation of Pex5p at a conserved cysteine residue, which contributes to the ATP-dependent release of the receptor from the membrane.

3.  Fractionation of the cytosol led to the discovery of four soluble transport factors that could, together with ATP, reconstitute nuclear import. One of these factors, importinα (also called karyopherinα, Kapα, and PTAC58), was shown to bind directly to an NLS, confirming the soluble receptor-carrier hypothesis.

First three option require ATP.

Last do not require ATP.