4-Dimethylaminoazobenzene interferes with the binding of ribosomes to reticular membranes.

Treatment of chemically degranulated rough endoplasmic reticulum (RER) with 4-dimethylamino-azobenzene (4-DAB) partly damages binding of fresh polyribosomes to both the lighter and heavier fractions of reconstituted RER. Also, treatment of ribosomes with 4-DAB seemed to inhibit their binding to the chemically stripped RER (DRER) appearing both as lighter and heavier rough membrane layers after reconstitution. The interaction of 4-DAB with stripped microsomal fraction and ribosomes might be introducing certain conformational constraints into their proteins, thus crippling the binding of the ribosomes to reticular membranes.