Telomere lengths and telomerase activity were studied during the development of a model dioecious plant, Melandrium album (syn Silene latifolia). Telomeric DNA consisted of Arabidopsis-type TTTAGGG tandem repeats. The terminal positions of these repeats were confirmed by both Bal31 exonuclease degradation and in situ hybridization. Analysis of terminal restriction fragments in different tissues and ontogenetic stages showed that telomere lengths are stabilized precisely and do not change during plant growth and development. Telomerase activity tested by using a semiquantitative telomerase repeat amplification protocol correlated with cell proliferation in the tissues analyzed. Highest activity was found in germinating seedlings and root tips, whereas we observed a 100-fold decrease in telomerase activity in leaves and no activity in quiescent seeds. Telomerase also was found in mature pollen grains. Telomerase activity in tissues containing dividing cells and telomere length stability during development suggest their precise control during plant ontogenesis; however, the telomere length regulation mechanism could be unbalanced during in vitro dedifferentiation.

Institute of Biophysics Czech Academy of Sciences Kralovopolska 135 612 65 Brno Czech Republic

Zobrazit více v PubMed

Methods Mol Biol. 1994;33:63-74 PubMed

Nature. 1990 May 31;345(6274):458-60 PubMed

Trends Biochem Sci. 1996 Oct;21(10):387-91 PubMed

Mol Gen Genet. 1996 Sep 13;252(3):342-5 PubMed

Proc Natl Acad Sci U S A. 1992 Nov 1;89(21):10114-8 PubMed

Nature. 1997 Feb 20;385(6618):740-3 PubMed

Proc Natl Acad Sci U S A. 1996 Dec 10;93(25):14422-7 PubMed

FEBS Lett. 1996 Aug 12;391(3):307-9 PubMed

Plant Mol Biol. 1995 Feb;27(3):467-75 PubMed

Nature. 1991 Apr 18;350(6319):569-73 PubMed

Science. 1995 Dec 8;270(5242):1601-7 PubMed

J Mol Biol. 1994 Jun 3;239(2):163-9 PubMed

Chromosome Res. 1997 Feb;5(1):57-65 PubMed

EMBO J. 1992 May;11(5):1921-9 PubMed

Cell. 1988 Apr 8;53(1):127-36 PubMed

Proc Natl Acad Sci U S A. 1995 Oct 10;92(21):9555-9 PubMed

Genetics. 1996 Dec;144(4):1893-901 PubMed

Exp Cell Res. 1995 Sep;220(1):194-200 PubMed

EMBO J. 1994 Jul 1;13(13):3211-7 PubMed

Science. 1997 Feb 14;275(5302):986-90 PubMed

Plant Cell. 1992 Aug;4(8):953-60 PubMed

Anal Biochem. 1976 May 7;72:248-54 PubMed

Science. 1997 Mar 7;275(5305):1478-81 PubMed

EMBO J. 1995 Sep 1;14(17):4240-8 PubMed

Proc Natl Acad Sci U S A. 1992 Feb 15;89(4):1354-7 PubMed

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

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

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

Homology-dependent repair is involved in 45S rDNA loss in plant CAF-1 mutants

Distribution of TTAGG-specific telomerase activity in insects

Telomere repeat binding proteins are functional components of Arabidopsis telomeres and interact with telomerase

A telomerase-independent component of telomere loss in chromatin assembly factor 1 mutants of Arabidopsis thaliana

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

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

Characterization of telomere-subtelomere junctions in Silene latifolia

Transition between two forms of heterochromatin at plant subtelomeres