Final answer:
Transposase is an enzyme that facilitates the movement of transposable elements within the genome. It cuts and ligates DNA to insert transposons into new genomic locations, generating direct repeats and ensuring genetic diversity.
Step-by-step explanation:
The function of transposase, which is associated with transposable elements within the genetic material, is immensely significant. More specifically, transposase is an enzyme that is adept at catalyzing the movement of DNA segments within the genome through various mechanisms such as cut-and-paste and replicative transposition. Among the listed options, the most accurate depiction of the role of transposase is to cut donor DNA outside the inverted terminal repeats (ITRs), to cut target DNA, and to ligate 3'-staggered ends between the transposon and the target DNA.
- It begins by making staggered cuts in the DNA, which includes nicking and trimming the 3'OH ends to excise the transposon.
- Then, it holds the transposon ends together and mediates its insertion at a new DNA site.
- After ligation of the 3'OH ends of the transposon to the 5'OH at the insertion site, replication fills in any missing bases, generating direct repeats of host cell genomic DNA at the insertion site.
- Finally, a ligation step completes the transposition process.
This complex and orchestrated sequence of events underscores the enzyme's pivotal role in ensuring genetic diversity and enabling adaptability by facilitating the movement of genetic elements within and across genomes.