Sequential activation of human signal recognition particle by the ribosome and signal sequence drives efficient protein targeting

Significance The universally conserved signal recognition particle (SRP) delivers ∼30% of the proteome to the appropriate cellular membrane. How SRP achieves efficient and selective protein targeting in eukaryotes remains elusive. Here, we show that a functional signal sequence on the nascent polypeptide confers a significant kinetic privilege to ribosome-bound SRP during the recruitment of SRP receptor, thereby enabling rapid and selective...