on the basis of a model of the translocation process to be described elsewhere , we propose an explanation of previous findings that the in vitro translocation across the endoplasmic reticulum of secretory proteins of higher eukaryotic cells appears to be obligatorily co-translational ( i.e. , occurs only while the polypeptide chain is being synthesized on the ribosome ) .
C1519614
translational
C0035553
ribosome