Accumulation of telomerase RNA and telomere protein transcripts during telomere synthesis in Euplotes.

In the ciliate Euplotes crassus a complex series of developmental events lead to formation of a new macronucleus. Millions of telomeres are synthesized during this process. We have shown that transcript levels are tightly regulated throughout Euplotes conjugation and macronuclear development. Thus, expression of gene products needed for macronuclear development and telomere synthesis appears to be controlled at the level of RNA abundance. To learn more about the role played by telomerase and the Euplotes telomere protein during telomere synthesis, we have correlated changes in the abundance of telomerase RNA and telomere protein mRNA transcript with specific developmental events. Telomerase RNA levels increase steadily during the early stages of macronuclear development and reach a peak just after telomere addition. The telomere protein transcript rises and falls twice during conjugation and then rises again at the time of telomere addition. The increases in transcript levels during conjugation parallel micronuclear division suggesting that the telomere protein is synthesized at this time and hence may have a micronuclear function.