- Ori (genetics)
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Ori is the DNA sequence that signals for the origin of replication, sometimes referred to simply as origin. In E. coli, ori is some 250 nucleotides in length for the chromosomal origin (oriC). The plasmid ori sequences are similar to oriC.
During conjugation, the rolling circle mode of replication starts at the oriT ('T' for transfer) sequence of the FAT plasmid.
Bacteria have a single origin for replication. Eukaryotes have multiple replicons, each with an ori. The replicons range from 40 kb (yeast and Drosophila) to 300 kb (plants) in length.
Mitochondrial DNA in many organisms has two ori sequences. In humans, they are called oriH and oriL for the heavy and light strand of the DNA, each is the origin of replication for single-stranded replication.
See also
References
- Lewin, Benjamin (2004). Genes VIII. Prentice Hall.
DNA replication (Prokaryotic, Eukaryotic) Separation
and initiationPre-replication complex: Origin recognition complex (ORC1, ORC2, ORC3, ORC4, ORC5, ORC6) · Minichromosome maintenance (MCM2 · MCM3 · MCM4 · MCM5 · MCM6 · MCM7) · CDC6
Autonomously replicating sequence
Single-strand binding protein (SSBP2, SSBP3, SSBP4)
RNase H (RNASEH1, RNASEH2A)
Helicase: HFM1
Primase: PRIM1 · PRIM2BothOrigin of replication/Ori/Replicon
Replication fork (Lagging and leading strands) · Okazaki fragment · PrimerReplication DNA polymerase III holoenzyme (dnaC, dnaE, dnaH, dnaN, dnaQ, dnaT, dnaX) · Replisome · DNA ligase · DNA clamp · Topoisomerase (DNA gyrase)
Prokaryotic DNA polymerase: DNA polymerase I (Klenow fragment)Replication factor C (RFC1) · Flap endonuclease (FEN1) · Topoisomerase · Replication protein A (RPA1)
Eukaryotic DNA polymerase: delta (POLD1, POLD2, POLD3, POLD4)
DNA clamp (PCNA)BothTermination Categories:- Genetics stubs
- DNA replication
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