11 Matching Annotations
  1. Nov 2022
    1. Can broadly split the process into three parts. Initiation, elongation and termination

    2. DNAPolymerase A

      Primase and DNA polymerase A work in close association.

    3. CDK2

      This is the S-phase CDK.

    4. Assembly of the pre-replicative complex
      • Replication origin licensing.
      • All of this occurs in G1 phase
    5. Orc complex

      Orc1-5 complex.

    6. Cdc6

      Cdc6 is only present in G1 phase.

    7. DNA replication pathway in humans. Orc complex binds the origin of replication.

    1. The initial sample consisted of 1 band. F = 0. 1st generation = The sample overall less dense, still one band. Intermediate density. dsDNA made of one strand heavy and one light. After 2 generations, there was a band for intermediate density and for strands of just light, N-14, dsDNA.

    2. Three methods of replication were initially hypothesized: * Conservative * Semi-conservative * Dispersive

      Semi-conservative method was eventually determined to be correct based on empirical evidence from Messelson & Stahl, in 1958.

    3. Parental strands consist of N-15 isotopes. Replicated daughter strands consist of N-14 isotopes. The CsCl ultracentrifugation process creates density gradient. This allows DNA fragments of different densities to migrate and form a band at the point at which their buoyant density equals that of the salt.

      1. E.coli grown in an heavy nitrogen, N-15, enriched medium
      2. Then transferred to N-14 based media to reproduce
      3. As several points in the experiment, cells were lysed and underwent ultracentrifugation through a CsCl concentration gradient