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. 2013 Sep 18;18(4):538–554. doi: 10.2478/s11658-013-0105-0

Telomerase and its extracurricular activities

Rishi Kumar Jaiswal 1, Pramod Kumar 1, Pramod Kumar Yadava 1,✉
PMCID: PMC6275585  PMID: 24048710

Abstract

The classical activity of telomerase is to synthesize telomeric repeats and thus maintain telomere length, which in turn ensures chromosome stability and cellular proliferation. However, there is growing evidence that implicates telomerase in many other functions that are independent of TERC being used as its template. Telomerase has an RNA-dependent RNA polymerase (RdRP) activity in the mitochondria. Other than viral RdRPs, it is the only RNA-dependent RNA polymerase that has been identified in mammals. It also plays a role in the Wnt signaling pathway by acting as a transcriptional modulator. Telomerase acts as a reverse transcriptase independent of its core subunit, TERC. Studies indicate that telomerase is also involved in apoptosis and DNA repair.

Key words: Telomerase, Telomere, RNA-dependent RNA polymerase, TERT, TERC, Apoptosis

Full Text

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Abbreviations used

BRG1

Brahma-related gene 1

PIP1

POT1-interacting protein 1

PTOP

POT1- and TIN2-organizing protein

RAP1

repressor and activator protein 1

RdRP

RNA-dependent RNA polymerase

SMARCA4

SWI/SNF-related matrix-associated actin-dependent regulator of chromatin, subfamily a, member 4

SWI/SNF

SWItch/sucrose non-fermentable

TEP1

telomerase-associated protein 1

TINT1

TIN2 Interacting Protein 1

TIN2 or TINF2

TRF1-interacting nuclear protein 2

TRF1 or TERF1

telomeric repeat-binding factor 1

TRF2 or TERF2

telomeric repeat-binding factor 2

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