Is DNA polymerase on the leading or lagging strand?
DNA polymerase I (pol I) processes RNA primers during lagging-strand synthesis and fills small gaps during DNA repair reactions.
Which DNA polymerase synthesizes the lagging strand?
Polymerase α
Polymerase α is found in a complex with primase, and it appears to function in conjunction with primase to synthesize short RNA-DNA fragments during lagging strand synthesis.
How does the DNA polymerase work on the leading and lagging strands?
The helicase unzips the double-stranded DNA for replication, making a forked structure. The primase generates short strands of RNA that bind to the single-stranded DNA to initiate DNA synthesis by the DNA polymerase. This enzyme can work only in the 5′ to 3′ direction, so it replicates the leading strand continuously.
Which DNA strand is leading and lagging?
The main difference between leading and lagging strand is that the leading strand is the DNA strand, which grows continuously during DNA replication whereas lagging strand is the DNA strand, which grows discontinuously by forming short segments known as Okazaki fragments.
Why does DNA replication have a leading strand and a lagging strand?
On the leading strand, DNA synthesis occurs continuously. On the lagging strand, DNA synthesis restarts many times as the helix unwinds, resulting in many short fragments called “Okazaki fragments.” DNA ligase joins the Okazaki fragments together into a single DNA molecule.
Which eukaryotic DNA polymerase synthesizes the leading strand?
Polymerase ε
Polymerase ε synthesizes DNA on the “leading” DNA strand continuously as it is pointing in the same direction as DNA unwinding by the replisome. In contrast, polymerase δ synthesizes DNA on the “lagging” strand, which is the opposite DNA template strand, in a fragmented or discontinuous manner.
Why does DNA have a lagging strand?
Why must there be a lagging strand during DNA synthesis? Explanation: The lagging strand exists because DNA is antiparallel and replication always occurs in the 5′ to 3′ direction.
Why does DNA synthesis occur differently on the leading and lagging strand?
Due to the antiparallel orientation of the two chromosomal DNA strands, one strand (leading strand) is replicated in a mostly processive manner, while the other (lagging strand) is synthesized in short sections called Okazaki fragments.
What causes the lagging strand to lag?
This delay occurs because DNA polymerization on the lagging strand is forced to occur in the direction going away from the replication fork. The fork thus must open up one Okazaki fragment’s length of DNA template before replication is initiation on that strand.
What is a lagging strand in DNA?
The lagging strand is a single DNA strand that, during DNA replication, is replicated in the 5′ – 3′ direction (opposite direction to the replication fork). DNA is added to the lagging strand in discontinuous chunks called ‘okazaki fragments’.