Dna Replication
DNA replication is a biological process that occurs in all living organisms and copies their DNA. DNA replication during mitosis is the basis for biological inheritance. The process of DNA replication starts when one double-stranded DNA molecule produces two identical copies of the molecule. Each strand of the original double-stranded DNA molecule serves as template for the production of the complementary strand, a process referred to as semiconservative replication. Cellular proofreading and error-checking mechanisms ensure near perfect fidelity for DNA replication.[1][2]
In a cell, DNA replication begins at specific locations, or origin of replication, in the genome.[3] Unwinding of DNA at the origin, and synthesis of new strands, forms a replication fork. A number of proteins are associated with the fork and assist in the initiation and continuation of DNA synthesis. Most prominently, DNA polymerase synthesizes the new DNA by adding matching nucleotides to the template strand.
DNA replication can also be performed in vitro (artificially, outside a cell). DNA polymerases isolated from cells and artificial DNA primers can be used to initiate DNA synthesis at known sequences in a template DNA molecule. The polymerase chain reaction (PCR), a common laboratory technique, cyclically apply such artificial synthesis to amplify a specific target DNA fragment from a pool of DNA.
Contents [hide] 1 Background on DNA structure
2 DNA polymerase
3 Replication process 3.1 Replication origin
3.2 Extensions
3.3 DNA replication proteins
3.4 Replication fork 3.4.1 Leading strand
3.4.2 Lagging strand
3.4.3 Dynamics at the replication fork
3.5 Regulation
3.6 Termination
4 Polymerase chain reaction
5 References
Background on DNA structure [edit]
DNA usually exists as a double-stranded structure, with both strands coiled together to form the characteristic double-helix. Each single strand of DNA is a chain of four types of nucleotides.
In a cell, DNA replication begins at specific locations, or origin of replication, in the genome.[3] Unwinding of DNA at the origin, and synthesis of new strands, forms a replication fork. A number of proteins are associated with the fork and assist in the initiation and continuation of DNA synthesis. Most prominently, DNA polymerase synthesizes the new DNA by adding matching nucleotides to the template strand.
DNA replication can also be performed in vitro (artificially, outside a cell). DNA polymerases isolated from cells and artificial DNA primers can be used to initiate DNA synthesis at known sequences in a template DNA molecule. The polymerase chain reaction (PCR), a common laboratory technique, cyclically apply such artificial synthesis to amplify a specific target DNA fragment from a pool of DNA.
Contents [hide] 1 Background on DNA structure
2 DNA polymerase
3 Replication process 3.1 Replication origin
3.2 Extensions
3.3 DNA replication proteins
3.4 Replication fork 3.4.1 Leading strand
3.4.2 Lagging strand
3.4.3 Dynamics at the replication fork
3.5 Regulation
3.6 Termination
4 Polymerase chain reaction
5 References
Background on DNA structure [edit]
DNA usually exists as a double-stranded structure, with both strands coiled together to form the characteristic double-helix. Each single strand of DNA is a chain of four types of nucleotides.
References: 2.^ a b Alberts B, Johnson A, Lewis J, Raff M, Roberts K, Walter P (2002). "Chapter 5: DNA Replication, Repair, and Recombination". Molecular Biology of the Cell. Garland Science. ISBN 0-8153-3218-1. 3.^ a b Berg JM, Tymoczko JL, Stryer L, Clarke ND (2002). "Chapter 27, Section 4: DNA Replication of Both Strands Proceeds Rapidly from Specific Start Sites". Biochemistry. W.H. Freeman and Company. ISBN 0-7167-3051-0. 4.^ Alberts, B., et.al., Molecular Biology of the Cell, Garland Science, 4th ed., 2002, pp. 238-240 ISBN 0-8153-3218-1 5.^ Allison, Lizabeth A 6.^ Berg JM, Tymoczko JL, Stryer L, Clarke ND (2002). Biochemistry. W.H. Freeman and Company. ISBN 0-7167-3051-0. Chapter 27, Section 2: DNA Polymerases Require a Template and a Primer 7.^ a b McCulloch SD, Kunkel TA (January 2008) 8.^ McCarthy D, Minner C, Bernstein H, Bernstein C (1976). "DNA elongation rates and growing point distributions of wild-type phage T4 and a DNA-delay amber mutant". J Mol Biol 106 (4): 963–81. PMID 789903. 9.^ Drake JW (1970) The Molecular Basis of Mutation. Holden-Day, San Francisco ISBN 0816224501 ISBN 978-0816224500 10.^ Alberts B, Johnson A, Lewis J, Raff M, Roberts K, Walter P (2002) 14.^ Griffiths A.J.F., Wessler S.R., Lewontin R.C., Carroll S.B. (2008). Introduction to Genetic Analysis. W. H. Freeman and Company. ISBN 0-7167-6887-9.[ Chapter 7: DNA: Structure and Replication. pg 283-290 ] 15.^ Pursell, Z.F 16.^ Hansen, Barbara (2011). Biochemistry and Medical Genetics: Lecture Notes. Kaplan Medical. p. 21. 17.^ Elizabeth R. Barry; Stephen D. Bell (12/2006). "DNA Replication in the Archaea". Microbiology and Molecular Biology Reviews 70 (4): 876–887. doi:10.1128/MMBR.00029-06. PMC 1698513. PMID 17158702. 23.^ Tobiason DM, Seifert HS (2006). "The Obligate Human Pathogen, Neisseria gonorrhoeae, Is Polyploid". PLoS Biology 4 (6): e185. doi:10.1371/journal.pbio.0040185. PMC 1470461. PMID 16719561. 25.^ TA Brown (2002). Genomes. BIOS Scientific Publishers. ISBN 1-85996-228-9.13.2.3. Termination of replication 26.^ Saiki, RK; Gelfand DH, Stoffel S, Scharf SJ, Higuchi R, Horn GT, Mullis KB, Erlich HA (1988)