User:Bhavani36/sandbox

= DNA Replication =

= The process of DNA duplication is called DNA replication. Replication follows several steps that involve multiple proteins called replication enzymes and RNA. The process of DNA replication is vital for cell growth, repair, and reproduction in organisms. = ·       Step 1: Replication Fork Formation - The replication fork is a region where a cell’s DNA-double helix has been unwound and seperated to create an area where DNA polymerases and the other enzymes involved can use each strand as a template to synthesize a new double helix.

·        Step  2: Primer Binding - The leading strand is the simplest to replicate. Once the DNA strands have been separated, a short piece of RNA called a primer binds to the 3’ end of the strand. The primer always binds as the starting point for replication. Primers are generated by the enzyme DNA primase.

·        Step 3: Elongation - During elongation, an enzyme called DNA polymerase adds DNA nucleotides to the 3’ end of the newly synthesized polynucleotide strand.

·       Step 4: Termination - The Termination of DNA replication occurs when two replication forks meet on the same stretch of DNA, during which the following events occur, though not necessarily in this order: forks converge until all intervening DNA is unwound; any remaining gaps are filled in and ligated; catenanes are removed; replication proteins are unloaded.

==== Requirements for DNA replication ==== ·       Original DNA template - DNA is a double helix made of two complementary strands. Each strand can be used as a template to create a new DNA molecule.

·       Free DNA nucleotides – needed to form the new strands.

·       DNA polymerase – an enzyme that adds new nucleotides to a growing strand of DNA.

·       Primers – A primer is a short strand of nucleotides that will bind to the 3’ end of the template DNA strand allowing DNA polymerase to add free DNA nucleotides.

References

·        https://pubmed.ncbi.nlm.nih.gov/23818497 

·        https://pubmed.ncbi.nlm.nih.gov/27542827 

·        https://pubmed.ncbi.nlm.nih.gov/27542827 

·        https://pubmed.ncbi.nlm.nih.gov/28537574