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Semi-quantitative Detection of RNA-dependent RNA Polymerase Activity of Human Telomerase Reverse Transcriptase Protein
Published on: June 12, 2018
Functional characterization of yeast telomerase RNA dimerization
Clay L Gipson1, Zhong-Tao Xin, Shamika C Danzy
1Department of Pathology and Laboratory Medicine, Experimental Pathology Division, Emory University School of Medicine, Atlanta, Georgia 30322, USA.
The Journal of Biological Chemistry
|May 11, 2007
Summary
Yeast telomerase RNA (TLC1) forms dimers, a feature conserved across viral and cellular reverse transcriptases. This dimerization, essential for telomere length maintenance, relies on specific RNA sequences.
Area of Science:
- Molecular Biology
- Genetics
- Biochemistry
Background:
- Telomerase, an RNA-dependent DNA polymerase, synthesizes telomeric DNA repeats at chromosome ends.
- Human telomerase RNA (hTERC) is hypothesized to function as a dimer.
- The role of dimerization in telomerase RNA function is not fully understood.
Purpose of the Study:
- To investigate whether yeast telomerase RNA (TLC1) forms dimers.
- To identify the sequence elements responsible for TLC1 dimerization.
- To determine the functional significance of TLC1 dimerization for telomere length.
Main Methods:
- In vitro dimerization assays for TLC1.
- Sequence analysis of TLC1 palindromic regions.
- Genetic analysis of dimerization-defective TLC1 alleles in yeast.
Main Results:
- Saccharomyces cerevisiae TLC1 forms dimers in vitro.
- TLC1 dimerization is mediated by a specific 6-base self-complementary sequence.
- Functional substitution of the S. cerevisiae dimerization palindrome by similar sequences from other yeasts.
- Yeast cells with dimerization-defective TLC1 exhibit shorter telomeres.
Conclusions:
- TLC1 dimerization is a conserved feature of telomerase RNA.
- RNA template dimerization is functionally important for telomere length maintenance.
- This dimerization mechanism is conserved between cellular telomerases and viral retroviral reverse transcriptases.
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