Wiech, Hans; Sagstetter, Maria; Müller, Günter; Zimmermann, Richard
The ATP requiring step in assembly of M13 procoat protein into microsomes is related to preservation of transport competence of the precursor protein.
In: The EMBO Journal Online, Vol. 6, No. 4: pp. 1011-1016
M13 procoat protein is processed to transmembrane coat protein by dog pancreas microsomes after completion of synthesis and in the absence of the signal recognition particle (SRP)/docking protein system. ATP is required for fast and efficient processing of procoat protein by microsomes in a reticulocyte lysate. Requirement for ATP is also observed in the absence of ribosomes or docking protein. This indicates the existence of a unique assembly pathway for procoat protein into microsomes which depends on ATP but does not depend on the SRP/docking protein and ribosome/ribosome receptor systems. We suggest that the ATP requirement is linked to a so far unknown component of the reticulocyte lysate, acting on transport competence of precursor proteins.