DNA replication - Revision history

Prab at 15:19, 10 November 2024

2024-11-10T15:19:36Z

← Older revision		Revision as of 15:19, 10 November 2024
Line 1:		Line 1:
	{{Short description\|Overview of the process of DNA replication in cells}}		{{Short description\|Overview of the process of DNA replication in cells}}
			[[File:DNA replication en.svg\|DNA replication\|500px\|right]]
	'''DNA replication''' is the biological process of producing two identical replicas of [[DNA]] from one original DNA molecule. This process occurs in all living organisms and is the basis for biological inheritance. DNA is made up of a double helix of two complementary strands. During replication, these strands are separated. Each strand of the original DNA molecule then serves as a template for the production of its counterpart, a process referred to as [[semiconservative replication]].		'''DNA replication''' is the biological process of producing two identical replicas of [[DNA]] from one original DNA molecule. This process occurs in all living organisms and is the basis for biological inheritance. DNA is made up of a double helix of two complementary strands. During replication, these strands are separated. Each strand of the original DNA molecule then serves as a template for the production of its counterpart, a process referred to as [[semiconservative replication]].

Prab at 15:18, 10 November 2024

2024-11-10T15:18:26Z

← Older revision		Revision as of 15:18, 10 November 2024
Line 1:		Line 1:
	{{Short description\|Overview of the process of DNA replication in cells}}		{{Short description\|Overview of the process of DNA replication in cells}}
	~~{{Use dmy dates\|date=October 2023}}~~
	~~{{Molecular biology}}~~

	'''DNA replication''' is the biological process of producing two identical replicas of [[DNA]] from one original DNA molecule. This process occurs in all living organisms and is the basis for biological inheritance. DNA is made up of a double helix of two complementary strands. During replication, these strands are separated. Each strand of the original DNA molecule then serves as a template for the production of its counterpart, a process referred to as [[semiconservative replication]].		'''DNA replication''' is the biological process of producing two identical replicas of [[DNA]] from one original DNA molecule. This process occurs in all living organisms and is the basis for biological inheritance. DNA is made up of a double helix of two complementary strands. During replication, these strands are separated. Each strand of the original DNA molecule then serves as a template for the production of its counterpart, a process referred to as [[semiconservative replication]].

Line 37:		Line 34:
	* [[Genetic recombination]]		* [[Genetic recombination]]
	* [[DNA repair]]		* [[DNA repair]]
			{{Molecular biology}}
			{{stub}}
	[[Category:Molecular biology]]		[[Category:Molecular biology]]
	[[Category:DNA replication]]		[[Category:DNA replication]]
	[[Category:Genetics]]		[[Category:Genetics]]

Prab: CSV import

2024-11-10T15:12:27Z

CSV import

New page

{{Short description|Overview of the process of DNA replication in cells}}
{{Use dmy dates|date=October 2023}}
{{Molecular biology}}

'''DNA replication''' is the biological process of producing two identical replicas of [[DNA]] from one original DNA molecule. This process occurs in all living organisms and is the basis for biological inheritance. DNA is made up of a double helix of two complementary strands. During replication, these strands are separated. Each strand of the original DNA molecule then serves as a template for the production of its counterpart, a process referred to as [[semiconservative replication]].

==Overview==
DNA replication begins at specific locations in the genome, called "origins". The unwinding of DNA at the origin, and synthesis of new strands, forms a replication fork. The process is initiated by the binding of a group of proteins to the origin, including [[helicase]], which unwinds the DNA, and [[primase]], which synthesizes a short RNA primer. DNA polymerases then extend the DNA strand from the RNA primer.

===Initiation===
The initiation of DNA replication involves the recognition of the origin of replication by initiator proteins. In [[prokaryotes]], this is often a single origin, while in [[eukaryotes]], there are multiple origins of replication. The initiator proteins recruit other proteins to form the [[pre-replication complex]].

===Elongation===
During elongation, the enzyme [[DNA polymerase]] synthesizes a new DNA strand by adding nucleotides complementary to the template strand. DNA polymerase can only add nucleotides to the 3' end of a DNA strand, so replication proceeds in the 5' to 3' direction. The leading strand is synthesized continuously, while the lagging strand is synthesized in short segments called [[Okazaki fragments]].

===Termination===
Termination of DNA replication occurs when two replication forks meet, or when the replication machinery reaches the end of a linear chromosome. In eukaryotes, the ends of linear chromosomes are protected by [[telomeres]], which are extended by the enzyme [[telomerase]].

==Enzymes involved==
Several key enzymes are involved in DNA replication:
* '''[[Helicase]]''' – unwinds the DNA double helix.
* '''[[Primase]]''' – synthesizes RNA primers.
* '''[[DNA polymerase]]''' – synthesizes new DNA strands.
* '''[[Ligase]]''' – joins Okazaki fragments on the lagging strand.
* '''[[Topoisomerase]]''' – relieves the tension caused by unwinding of DNA.

==Errors and proofreading==
DNA replication is a highly accurate process, but errors can occur. DNA polymerases have proofreading abilities that allow them to correct mistakes by removing incorrectly paired nucleotides. Additional repair mechanisms, such as [[mismatch repair]], further increase the fidelity of DNA replication.

==Significance==
DNA replication is essential for [[cell division]], allowing genetic information to be passed from one generation to the next. Errors in replication can lead to [[mutations]], which may result in [[genetic disorders]] or contribute to the development of [[cancer]].

==Also see==
* [[Central dogma of molecular biology]]
* [[Transcription (biology)]]
* [[Translation (biology)]]
* [[Genetic recombination]]
* [[DNA repair]]

[[Category:Molecular biology]]
[[Category:DNA replication]]
[[Category:Genetics]]