Question

Telomerase is an unusal DNA polymerase in that it carries its own short segment of RNA to assist in DNA synthesis.

b.Why would this not be a good strategy for other DNA polymerases used to replicate the remainder of the genome?

Answer 1

Telomerase is a reverse transcriptase enzyme that has it's own RNA segment to elongate the telomeres during the DNA replication. It is a RNA-dependent DNA polymerase. Other DNA polymerases do not carry then own segment of RNA because most of them are mostly DNA dependant DNA polymerases, that is they synthesize new DNA strands from the pre-existing ones. Carrying their own RNA segments may prove hazardous as the RNA segments won't leave the sight after the replication or repair processes. Most DNA polymerases are involved in host replication and repair processes and not in viral replication like the Telomerase enzyme. DNA polymerases carrying their own RNA segments would give rise to unwanted errors in the replication procedure or will not allow proper proofreading mechanisms. The extra RNA segment if present with the polymerases, would not allow proper ligation of the polymerase to the DNA strands during replication. Telomerase actually is useful to preventing the aging of cells and also is active in most cancer cells.