Reverse Transcription

Telomeres are found in prokaryotes.

Reverse transcription is the process of converting DNA to RNA.

Telomeres are produced as a result of complete replication at the end of the chromosomes.

Telomeres are present at the centromere of chromosomes in eukaryotic organisms.

Reverse transcription is a mechanism used by eukaryotic cells to synthesize proteins.

Telomeres ensure that the chromosomes stick together.

Telomeres play a vital role in ageing.

Telomerase enzyme can decrease the length of telomeres.

The enzyme reverse transcriptase is used by eukaryotic cells to replicate their genomes.

Telomeres contain coding sequences that are rich in Adenine nucleotides.

The repeating sequence in humans is 5'-TTTAGGG-3'.

Telomeres and their Structure

Telomeres are found in birds, reptiles, amphibians, fishes, and mammals, with the common tandem repeat of TTAGGG.
They are composed of short nucleotide sequences that are repeated multiple times and do not code for any protein.
In humans, the repetitive sequence is 5'-TTAGGG-3', which is repeated multiple times, whereas in plants, it is TTTAGGG.

Role of Telomeres

Telomeres are produced as a result of incomplete replication at the end of chromosomes, ensuring that genetic information is preserved and not lost.
They act as protective end caps, preventing chromosomes from sticking together and protecting from deterioration.
Telomeres play a vital role in ageing, with each replication cycle resulting in shorter telomeres, eventually leading to senescence and apoptosis when they become too short.

Telomerase Enzyme

Telomerase is a special enzyme that can increase the length of telomeres.
It is present in cells that divide unlimited times, such as unicellular eukaryotes, egg and sperm cells, blood cells, and cancer cells.

Reverse Transcription

Reverse transcription is the conversion of RNA to DNA, where RNA acts as the template in the synthesis of complementary DNA (cDNA).
The central dogma defines the mechanisms that involve DNA synthesis, RNA synthesis, protein synthesis, and cDNA synthesis.
Reverse transcriptases are used by viruses such as HIV and hepatitis B to replicate their genomes.
The conversion of RNA to DNA is commonly used as a diagnostic tool in laboratory settings for RNA viruses such as HIV, hepatitis, influenza, and coronaviruses.

Learn about the process of reverse transcription, where RNA is converted to DNA to produce complementary DNA (cDNA). Understand how this process relates to the central dogma of molecular biology and how RNA can also code for DNA in certain circumstances.