Telomerase regulation at the telomere: a binary switch.
Telomerase is known to preferentially elongate the shortest telomeres in a cell. Using an elegant yeast assay, Texeira et al. (2004 [this issue of Cell]) address what aspect of telomerase action is regulated by telomere length: the frequency or the extent of telomere elongation. They show that short telomeres are elongated more frequently than long telomeres, arguing that telomeres switch between two states, one that allows telomere extension and one that does not.
Loayza
Diego
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Laboratory for Cell Biology and Genetics, The Rockefeller University, 1230 York Avenue, New York, NY 10021, USA.
de Lange
Titia
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D003433:Crosses, Genetic; D015971:Gene Expression Regulation, Enzymologic; D015966:Gene Expression Regulation, Fungal; D005800:Genes, Fungal; D014644:Genetic Variation; D011995:Recombination, Genetic; D012441:Saccharomyces cerevisiae / Q000201:enzymology* / Q000235:genetics; D019098:Telomerase / Q000172:deficiency / Q000235:genetics / Q000378:metabolism*; D016615:Telomere / Q000235:genetics* / Q000378:metabolism
D019098:Telomerase