THE MOLECULAR BASIS OF INHERITANCE
DNA MAKES RNA MAKES PROTEIN
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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DNA ligase
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DNA polymerase I
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RNA primase
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DNA helicase
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Detailed explanation-1: -There is compelling evidence that DNA ligase I is predominantly responsible for joining Okazaki fragments generated by discontinuous DNA synthesis on the lagging strand at the replication fork.
Detailed explanation-2: -These small pieces of newly synthesized DNA (called Okazaki fragments after their discoverer) are joined by the action of DNA ligase, forming an intact new DNA strand.
Detailed explanation-3: -Thus, we propose that after Okazaki fragment DNA synthesis is completed by a PCNA-DNA pol delta complex, DNA pol delta is released, allowing DNA ligase I to bind to PCNA at the nick between adjacent Okazaki fragments and catalyze phosphodiester bond formation.
Detailed explanation-4: -Ultimately, the Okazaki fragments are joined together by an enzyme DNA ligase.
Detailed explanation-5: -The Okazaki fragments must be attached together into one continuous strand after replication. This is accomplished by the enzyme DNA ligase, which seals the sugar phosphate backbone of the Okazaki fragments. This allows for replication of two, continuous identical daughter strands of DNA.