The mechanism of spacer sequence acquisition is as
Each new spacer sequence is inserted next to the leader sequence, with the consequence that the array is a temporal record of acquisitions past. The sequence destined to become spacer is, within the phage genome, known as a “proto-spacer” and lies adjacent to a PAM sequence
#Unit 3. Fundamental Processes#mRNA stability, transport, CRISPR, miRNA & siRNA#Part B Pointers