Regulation of DNA Replication

Content of Nucleic Acid Synthesis
» Nucleic Acids
» Structure and Function of Nucleic Acids
    » Basic Chemical Structure
    » Base Pairing in Nucleic Acids: Double Helical Structure of Dna
    » Size, Structure, Organization, and Complexity of Genomes
    » Information Storage, Processing, and Transfer
    » Chromosomal Dna Compaction and Its Implications in Replication and Transcription
    » DNA Sequence and Chromosome Organization
    » Repetitive Sequences: Selfish DNA
    » Chromatin Remodeling and Histone Acetylation
» Nucleic Acid Syntheses
    » Similarity of DNA and RNA Synthesis
    » DNA Replication Vs Transcription: Enzymatic Processes
    » Multiplicity of DNA and RNA Polymerases
» DNA Replication and Its Regulation
    » DNA Replication
    » Regulation of DNA Replication
    » Regulation of Bacterial DNA Replication at the Level of Initiation
    » DNA Chain Elongation and Termination in Prokaryotes
    » General Features of Eukaryotic DNA Replication
    » Licensing of Eukaryotic Genome Replication
    » Fidelity of DNA Replication
    » Replication of Telomeres—The End Game
    » Telomere Shortening: Linkage Between Telomere Length and Limited Life Span
» Maintenance of Genome Integrity
» DNA Manipulations and their Applications
» Transcriptional Processes
    » Recognition of Prokaryotic Promoters and Role of S-Factors
    » Regulation of Transcription in Bacteria
    » Eukaryotic Transcription
    » RNA Splicing in Metazoans
    » Regulation of Transcription in Eukaryotes
    » Fidelity of Transcription (RNA Editing)
» Chemical Synthesis of Nucleic Acids (Oligonucleotides)
» Bibliography of Nucleic Acid Synthesis
Semi-conservative replication of the genome ensures that each daughter cell receives a full complement of the genome prior to cell division. In eukaryotes, this is achieved by the distinct phases of the cell cycle, namely, G1 phase, during which cells prepare for DNA synthesis; S phase, in which DNA replication is carried out; and G2- M (mitosis), during which the replicated chromosomes segregate into the two newly divided daughter cells. Unlike in eukaryotes, DNA replication in prokaryotes may occur continuously during growth (in rich medium). Thus, the copy number of genomes could exceed two in rapidly growing cells. In the case of viruses, which multiply by utilizing the host cell synthetic machinery and eventually killing them, genome replication may be not controlled. However, plasmid DNA, as well as the genomes of organelles such as mitochondria and chloroplasts, is replicated with some degree of regulation. In these cases the genomic copy number can vary within limits as a function of growth condition.