Why do prokaryotic cells not have telomeres?
The “end replication problem” is exclusive to linear chromosomes as circular chromosomes do not have ends lying without reach of DNA-polymerases. Most prokaryotes, relying on circular chromosomes, accordingly do not possess telomeres.
Do all cells have telomerase?
Most human somatic cells do not produce active telomerase and do not maintain stable telomere length with proliferation. Most or all do have telomerase RNP, which raises the possibility of a second telomerase function independent of DNA synthesis.
Why do bacterial cells not need telomeres?
Bacteria don’t need telomerase because their chromosomes don’t have telomeres. Most bacterial chromosomes are circular, meaning they have no end.
Why do somatic cells not have telomerase?
Telomerase activity is absent in most normal human somatic cells because of the lack of expression of TERT; TERC is usually present. … The absence of telomerase activity in most human somatic cells results in telomere shortening during aging.
Why are telomeres needed in eukaryotes but not prokaryotes?
Telomeres are only present in eukaryotes. This is the case because eukaryotes are the only type of cell that contains linear DNA. There are telomeres on each end of the chromosomes within the nucleus of these cells. Prokaryotes, on the other hand, have a single circular strand of DNA within a nucleoid.
Why are telomeres needed in eukaryotes and not prokaryotes?
Unlike prokaryotic chromosomes, eukaryotic chromosomes are linear. … The ends of the linear chromosomes are known as telomeres, which have repetitive sequences that code for no particular gene. In a way, these telomeres protect the genes from getting deleted as cells continue to divide.
What happens if we don’t have telomerase?
Without telomerase activity, these cells would become inactive, stop dividing and eventually die. Drugs that inhibit telomerase activity, or kill telomerase-producing cells, may potentially stop and kill cancer cells in their tracks. … However, telomerase activity in somatic cells is very low.
How can telomerase be inhibited?
One of the oldest and most commonly used classes of telomerase inhibitory agents is antisense DNA oligonucleotides. The use of antisense molecules to block the translation of mRNA into a functional protein has been commonly used since the 1990s.