Controlled termination of replication

DNA Is Usually Sequenced by Controlled Termination of Replication (Sanger Dideoxy Method)... 

Northern blotting (p. 146) controlled termination of replication (Sanger dideoxy method) (p. 146) polymerase chain reaction (PCR) (p, 149) vector (p. 152) plasmid (p. 152)... 

The stages of DNA replication in bacteria are initiation, elongation, and termination. Control of replication is effected at the level of initiation. Thus, the frequency of initiation determines the frequency of completion of cycles of replication. The rate of replication-fork movement (elongation) remains fairly constant under conditions that change the overall rate of replication. There is no evidence to suggest that termination has any control over the rate of replication. 

The pWHA43 plasmid contains 3.9 kbp and replicates with the pMBl origin of replication. The plasmid was constructed with an insert of cDNA encoding met-prochymosin under the control of a tandem lac-trp promotor operator arrangement as described in (1). The prochymosin gene was inserted just upstream from the ampicillin resistance gene without a transcription terminator sequence between, but with the RNA polymerase binding site for amp also intact, so that presumably amp is transcribed from both the lac-trp and natural amp promotors. 

The plausibility of the above mechanism was established by comparing to data the model s predictions of the length of the C period (the time to replicate a whole new DNA molecule) and D period (the time from the termination of the chromosome synthesis to the next cell division) and the timing of Initiation. The results are given in Tables V and VI. Other mechanisms (e.g. positive control due to build-up of DNA precursors, to the rate of cell envelope synthesis, to the mass of the cell envelope, or to the total cell mass) have been shown to be implausible when tested for growth under glucose limitation (46). The form of the equations for the glucose-limited cell have been justified (46,... 

Control regions, which promote or enhance the expression of individual genes, and include regions which respond to hormones and other factors which control gene expression (section 10.4), as well as sites for the initiation and termination of DNA replication. 

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