RT Journal Article
SR Electronic
T1 Developmental Control of Telomere Lengths and Telomerase Activity in Plants
JF The Plant Cell
JO Plant Cell
FD American Society of Plant Biologists
SP 1691
OP 1698
DO 10.1105/tpc.10.10.1691
VO 10
IS 10
A1 Riha, Karel
A1 Fajkus, Jiri
A1 Siroky, Jiri
A1 Vyskot, Boris
YR 1998
UL http://www.plantcell.org/content/10/10/1691.abstract
AB 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.