Disruption of the telomerase catalytic subunit gene from Arabidopsis inactivates telomerase and leads to a slow loss of telomeric DNA

• DOI: 10.1073/pnas.96.26.14813
• Publication Date: 2002-07-26T14:43:20Z
• Authors: Matthew S. Fitzge...; Karel Riha; Feng Gao; Shuxin Ren; Thomas D. McKnight; Dorothy E. Shippen
• Keywords: Telomerase RNA component

Telomerase is an essential enzyme that maintains telomeres on eukaryotic chromosomes. In mammals, telomerase required for the lifelong proliferative capacity of normal regenerative and reproductive tissues sustained growth in a dedifferentiated state. Although importance was first elucidated plants 60 years ago, little known about role plant development. Here we report cloning characterization Arabidopsis reverse transcriptase (TERT) gene, AtTERT. AtTERT predicted to encode highly basic protein 131 kDa harbors telomerase-specific motifs common all TERT proteins. mRNA 10–20 times more abundant callus, which has high levels activity, versus leaves, contain no detectable telomerase. Plants homozygous transfer DNA insertion into gene lack confirming identity function this gene. Because wild-type are short, discovery telomerase-null viable at least two generations unexpected. absence telomerase, decline by approximately 500 bp per generation, rate 10 slower than seen telomerase-deficient mice. This gradual loss telomeric may reflect reduced nucleotide depletion round replication, or requirement fewer cell divisions organismal generation. Nevertheless, progressive telomere shortening mutants, however slow, ultimately should be lethal.