Diverse and dynamic functions of the Sir silencing complex
L Guarente
Department of Biology, Massachusetts Institute of Technology
, Cambridge, Massachusetts, USA.
leng@mit.edu
The yeast Sir protein complex has been implicated in transcriptional silencing
and suppression of recombination. The Sir complex creates structured chromosomal
domains at telomeres, silent mating-type loci and ribosomal DNA to invoke
these functional states. Mechanistic insights into the function of Sir proteins
implicate a range of activities in yeast, including repair of DNA double-strand
breaks, regulation of the mitotic cell cycle, meiosis and ageing. I speculate
that the Sir proteins may be capable of enzymatic modification of chromatin
and other substrates, which enables them to carry out a broad range of cellular
functions.
