Studies of the single cell ciliate Tetrahymena thermophila have provided many insights into telomere structure and function. Telomeres, repetitive sequences at the chromosomal termini, are critical for the stabilization of chromosomes. Telomeres also play important roles in both cancer and aging. Tetrahymena is an excellent system for studying telomeres since each cell possesses more than 40,000 telomeres. One significant drawback of using this organism is that the transformation vectors currently available are relatively rudimentary. The creation of a novel vector, which would exist as an episome, would allow for a more complete investigation of telomere biology. The construction of an artificial chromosome in Tetrahymena thermophila would be a major step in improving complementation analysis in this model organism
