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Definition
| semiconservative, begins at origin of replication and proceeds bidirectionally, synthesis proceeds in 5' to 3' direction and is semi-discontinuous |
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Definition
| each DNA strand acts as template resulting in 2 double-stranded DNA each containing one new and one old strand (meselson-stahl experiment) |
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Term
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Definition
| always start at same place (A-T rich site) on DNA = origin, bacteria - 1 origin, us >1 origin |
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Term
| direction of DNA replication |
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Definition
| always 5'->3', continuous on 5'-3' strand, semi-discontinuous on 3'-5' strand |
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Term
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Definition
| strand synthesized continuously in 5'->3' strand |
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Term
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Definition
| lagging strand is synthesized in short fragments in 5'->3' as replication fork opens, then fragments are linked by DNA ligase |
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Term
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Definition
| synthesizes DNA from a primed DNA template, Mg-dependent, will only accommodate correctly matched base pairs, all have 3'->5' exonuclease activity, some have 5'->3' |
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Term
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Definition
| DNase that degrades nucleic acid from free ends, 5'->3' or 3'->5' activity |
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Term
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Definition
| DNase that degrades nucleic acid from internal sites |
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Term
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Definition
| links 5' and 3' ends of DNA with phosphodiester bond |
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Term
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Definition
| if base is mismatched, polymerase stalls, exonuclease removes incorrect base, and replication starts again |
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Term
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Definition
| clean-up and repair, slow (16-20/sec), low processivity (3-200 bases before disassociates) |
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Term
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Definition
| principal replication enzyme, fast (adds 250-1000/sec), high processivity (500,000 bases added before dissociation), NO 5'->3' activity |
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Term
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Definition
| important protein complex with DNA polymerase I and III, helicase, topoisomerase, DNA binding proteins, primase, ligase |
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Term
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Definition
| A=T rich site, helicase unwinds, binding protein stabilizes, topoII relieves helical tension, the only step in prokaryotes that is regulated |
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Term
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Definition
| leading strand-primase adds primer, dNTPs added to primer by pol III; lagging strand-primers added dNTPs polymerized until reach the next primer, pol III dissociates and pol I removes RNA primer, adds correct dNMPs and seals nick with DNA ligase; pol III is dimer and both strands rplicated by 1 pol III dimer in coordinated fashion |
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Term
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Definition
| ermination sequences halt replication in both directions, topo iV separates catenated (interlinked circles) DNA |
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Term
| bacterial DNA replication |
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Definition
| RNA primer required, pol I and III require Mg, all 4 dNTPs, and DNA template strand, 5'->3' until termination sequence |
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Term
| eukaryotic DNA replication |
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Definition
| multiple origin, histones - slower, very organized structure, telomere terminates replication (no ter sequence b/c not circular), more DNA polymerase |
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Term
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Definition
| extends parent strand beyond telomere that is then synthesized by DNA polymerase using RNA as a primer, a reverse transcriptase leading to RNA dependent DNA replication, not found in normal human cells, is found in sperm/egg cells, cancer cells up-regulate it |
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Term
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Definition
| contains DNA or RNA (not both), depend on host cell for replication, DNA viruses encode their own DNA polymerase (b/c host cells won't have RNA->RNA polymerase) |
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Term
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Definition
| induce cell death (HIV, T cell death), prevent cell death (cowpox, crmA), undergo malignant transformation (HPV, cervical cancer), chronic latent/silent infection and re-emerge later (integrate into host genome), chronic infections (hepatitis) |
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Term
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Definition
| poliovirus, mRNA, can be immediately translated into protein (via RNA-dependent RNA polymerase), life cycle in cytoplasm |
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Term
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Definition
| influenza, measles, mumps, rabies, must be converted into +RNA by RDRP contained within virion, life cycle in cytoplasm |
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Term
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Definition
| parvovirus, herpes, pox viruses, DNA transcribed by host proteins to produce mRNAs, may be integrated into host genome (not adenovirus) |
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Term
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Definition
| HIV, +RNA->DNA by viral reverse transcriptase-RDDP, dsDNA often integrates into host genome, can be latent |
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Term
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Definition
| halt chain elongation, prodrugs, guanine analogs: gancyclovir and acyclovir (greater affinity for viral thymidine kinase) |
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Term
| NTP or dNTP nucleotide analogs |
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Definition
| inhibit viral DNA polymerase, lack 3'OH chain termination |
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