Functions of telomers that functions to maintain and lengthening of telomeres, the tandem repetitive DNA sequences located at the ends of human chromosomes.

A holoenzyme made up of human telomerase reverse transcriptase, an RNA template, and specialized proteins, that participates in the synthesis of telomeres and maintenance of the telomere length in rapidly dividing cells.

A ribonucleoprotein enzyme complex that builds new telomere sequences onto the ends of chromosomes.

Composed of the telomerase reverse transcriptase and its RNA template.

It is associated with other proteins that help in telomere assembly, trafficking, recruitment, and stability.

The two essential function of telomeres are protecting chromosome ends and facilitates their complete replication.

Elevated levels expressed in almost all human tumors.

Active in most cancer cells but not in normal somatic tissue.

Urine telomerase activity elevated in early bladder cancer.

Has 2 essential components telomerase reverse transcriptase , a catalytic component, and an RNA component which provides the template for nucleotide addition by telomerase reverse transcriptase.

Telomeres-TTAGGG DNA repeats at the end of chromosomes.

Regarded as the internal biological clock because they shorten with every cell division.

The addition of telomeric repeats onto the ends of chromosomes partly offsets the shortening that occurs during DNA replication.

Telomeres in blood cells contain about 10,000-20,000 nucleotides at birth.

Telomeres reduces by about 50-150 bp per year with a reduction to a few thousand bp in the elderly.

Gerline mutations that impact the telomere complex can lead to loss of telomeres during cell replication, shortening the stem cell pool.

Regeneration stresses that occur in patients with bone marrow failure, chemotherapy, or hematopoetic stem cell transplant can enhance telomere shortening secondary to increased mitotic activity.

Reactive oxygen species generated secondary to inflammation, toxins or radiation exposure can cause DNA damage and telomere loss.

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