Which of the following best describes a signaling pathway in response to unfolded proteins in the endoplasmic reticulum (ER)?
a. Unfolded proteins in the ER translocate into the cytosol, where they activate HSF1 to allow for refolding in the cytosol.
b. Unfolded proteins in the ER activate ATF6. AT then loses interaction with KEAP1, allowing it to translocate into the nucleus and activate the expresion of ER chaperone
c. Unfolded proteins in the ER activate ATF4, which enhances protein translation, so that at least some of the proteins that are folded in the ER will be folded correctly.
d. IRE1 is activated by unfolded proteins in the ER and then allows for splicing to create XBP1, which allows for the transcription of ER chaperones.
