Which of the Following Is Not a Characteristic of Immunoproteasomes

Multiple Choice

Which of the following is not a characteristic of immunoproteasomes?

A) They make up about 1% of cellular protein.
B) They consist of four rings of seven polypeptide subunits that exist in alternative forms.
C) They are produced in response to IFN-γ produced during innate immune responses.
D) They produce a higher proportion of peptides containing acidic amino acids at the carboxy terminus compared with constitutive proteasomes.
E) They contain 20S proteasome-activation complexes on the caps.