Telomerase is a ribonucleoprotein enzyme which elongates the G-rich strand of telomeric DNA to compensate for the progressive reduction in its length due to incomplete replication of chromosome ends, which in human somatic cells leads to cell cycle arrest upon shortening of telomeres to a critical length. To examine the possible involvement of telomerase in metabolism of plant genetic material, we used cells of Nicotiana tabacum strain TBY-2, a stable long-term culture which has kept a constant pattern of restriction fragments from chromosome termini during its 6 month period of cultivation in our laboratory. In a direct assay for telomerase, a 5' end-labeled plant telomeric oligonucleotide 5' (TTTAGGG)(3')6 was elongated in a TBY-2 cell extract, showing a pausing pattern which is a characteristic feature of telomerases from other organisms. The elongation was inhibited by RNase A pretreatment of the extract. We conclude that plant cells possess telomerase which is used for maintenance of their telomeres.

Institute of Biophysics Academy of Sciences of the Czech Republic Czech Republic

Citace poskytuje Crossref.org

Telomerase RNA evolution: a journey from plant telomeres to broader eukaryotic diversity

Telomeres and Their Neighbors

Composition and Function of Telomerase-A Polymerase Associated with the Origin of Eukaryotes

Tidying-up the plant nuclear space: domains, functions, and dynamics

Telomerase RNAs in land plants

Telomeres in Plants and Humans: Not So Different, Not So Similar

Telomere elongation upon transfer to callus culture reflects the reprogramming of telomere stability control in Arabidopsis

An armadillo-domain protein participates in a telomerase interaction network

Tissue-specific expression of telomerase reverse transcriptase gene variants in Nicotiana tabacum

Telomere- and Telomerase-Associated Proteins and Their Functions in the Plant Cell

Telomere dynamics in the lower plant Physcomitrella patens

Developmental silencing of the AtTERT gene is associated with increased H3K27me3 loading and maintenance of its euchromatic environment

Three TERT genes in Nicotiana tabacum

Hypomethylating drugs efficiently decrease cytosine methylation in telomeric DNA and activate telomerase without affecting telomere lengths in tobacco cells

Role of alternative telomere lengthening unmasked in telomerase knock-out mutant plants

Asparagales telomerases which synthesize the human type of telomeres

Developmental control of telomere lengths and telomerase activity in plants