In budding yeast, the telomeric DNA is flanked by a combination of two 
subtelomeric repetitive sequences, the X and Y' elements. We have investigated 
the influence of these sequences on telomeric silencing. The telomere-proximal 
portion of either X or Y' dampened silencing when located between the telomere 
and the reporter gene. These elements were named STARs, for subtelomeric 
anti-silencing regions. STARs can also counteract silencer-driven repression at 
the mating-type HML locus. When two STARs bracket a reporter gene, its 
expression is no longer influenced by surrounding silencing elements, although 
these are still active on a second reporter gene. In addition, an intervening 
STAR uncouples the silencing of neighboring genes. STARs thus display the 
hallmarks of insulators. Protection from silencing is recapitulated by 
multimerized oligonucleotides representing Tbf1p- and Reb1p-binding sites, as 
found in STARs. In contrast, sequences located more centromere proximal in X and 
Y' elements reinforce silencing. They can promote silencing downstream of an 
insulated expressed domain. Overall, our results suggest that the silencing 
emanating from telomeres can be propagated in a discontinuous manner via a 
series of subtelomeric relay elements.