Strand elongation

Enzyme Taq polymerase (or some other enzyme) adds new deoxyribonucleotides during strand elongation. Taq is added to the assay at 1 unit per 50 qL of reaction mixture. 

Antipyrimidine antimetabolite inhibits DNA polymerase with inhibition of DNA strand elongation and replication activated in tumor cells in triphosphate form competes with conversion of cytidine to deoxycytidine nucleotides, further blocking polymerization of DNA leads to production of short DNS strands cell-cycle specific (S phase) acts only on proliferating cells. 

DNA polymerase 5 - leading strand and lagging strand elongation. 

Cytarabine (ara-C) is an arabinose analog of cytosine. Cytarabine was originally isolated from sponges, but is now produced synthetically. Ara-C is phosphorylated to its active triphosphate form (ara-CTP) within tumor cells. Ara-CTP inhibits DNA polymerase, an enzyme responsible for strand elongation. It is also incorporated directly into DNA, where it inhibits the replication of DNA and acts as a chain terminator to prevent DNA elongation. Activation of ara-C is opposed by deaminase enzymes, particularly cytidine deaminase, which degrades ara-C to an inactive form, ara-U. " " ... 

After several ribonucleotides have been polymerized, RNA polymerase dissociates from the promoter DNA and general transcription factors. During the stage of strand elongation, RNA polymerase moves along the template DNA one base at a time, opening the double-stranded DNA In front of Its direction of movement and hybridizing the strands behind... 

The conformational change produced by these drugs results in altered strand elongation and interferes with DNA polymerase activity. Protein synthesis is also inhibited because of the effects on RNA polymerase. 

If the MA-linked YPg dissociates from the MA polymerase after initiation of MA synthesis, strand elongation could occur in the absence of the initiator" protein. As a consequence the nascent strand may anneal to template MA and generate double-stranded MA (EF). 

The return strand of chain conveyors usually needs to be supported when the conveyor is more than 15 feet long. That is because an unsupported return strand, hanging as a catenary, can greatly increase the chain pull. The chain pull normally will be much less when the return strand is supported. In addition, the sag in a return strand elongated from wear sometimes will hang up on obstructions the chain cleared when the conveyor was new. Supporting the return strand also will minimize pulsation and whip. 

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