Question

Describe the process of DNA replication in a well-organized manner. Start with the helicase and go through the entire process, step by step. Use these terms correctly: Helicase, DNA primase, single stranded binding proteins, DNA polymerase I, DNA Polymerase III, leading strand, lagging strand, okazaki fragments, ligase, topoisomerase, sliding clamp, clamp loader. Please use correct descriptions of the enzyme function. For example, do not say, “seals nicks.” Tell me what “seals nicks” means. If you speak about something you have not studied in the notes, then you must cite your sources. Also, this assignment must be in your own words.

Answer 1

Question

The steps of DNA replication in a sequential manner are following :

I. DNA unwinds at the specific site on the DNA known as origin of replication.

II. The enzyme helicase start unwinding the double stranded DNA and form replication fork.

III. The single stranded binding protein bind to open DNA strands so to prevent rewinding of the DNA.

IV. The enzyme topoisomerase bind to the DNA polymerase to prevent any further binding of the DNA.

V. Then primase enzyme start synthesizing RNA primer complementary to the DNA molecule.

VI. DNA polymerase III enzyme start to synthesis complementary DNA nucleotide in 3'OH direction.

VII. The strand 5'->3' direction of parent strand is known as template strand and 3'->5' is known as lagging strand.

VI. DNA sliding camp complex protein bind to DNA polymerase in order to prevent its dissociation from the template strand.

VII. The small fragments of DNA synthesized in DNA strand are known as lagging strand.

VIII. Elongation of both leading and lagging strand continue.

IX. RNA primers are removed by the DNA polymerase I enzyme.

X. The DNA fragments get join by DNA ligase enzyme.