Transfer of proteins across membranes. I. Presence of proteolytically processed and unprocessed nascent immunoglobulin light chains on membrane-bound ribosomes of murine myeloma. II. Reconstitution of functional rough microsomes from heterologous components.

"In 1975 Günther Blobel showed that in certain cases amino acids in a protein serve as an address label that determines where a protein is to be delivered. Amino acid sequences determine whether a protein is to be passed through the membrane out of the cell or into an organelle or is to be built in the membrane." (Nobel website).

In 1999 Günter Blobel was awarded the Nobel Prize in Physiology or Medicine "for the discovery that proteins have intrinsic signals that govern their transport and localization in the cell."

See also: Simon, Sanford M. and Blobel, "A protein-conducting channel in the endoplasmic reticulum," Cell, 65, 1991, 371-380.
See also: Sanford M. Simon, "Obituary: Günther Blobel (1936-2018)," Cell, 173, 2018, 278-280. Available from PubMedCentral at this link.