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Diverse and dynamic functions of the Sir silencing complex

Nature Genetics volume 23, pages 281–285 (1999)Cite this article

Abstract

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.

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Figure 1: Functions of Sir proteins.
Figure 2: Distribution of the Sir repairosome to double-strand breaks.
Figure 3: Nucleolar sequestration of Cdc14p regulates exit from anaphase.
Figure 4: Sir proteins extend lifespan in yeast.

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Acknowledgements

I thank colleagues in the field for stimulating discussions. Work from my laboratory was supported by grants from the NIH, the Seaver Institute, The Ellison Medical Foundation, and The Howard and Linda Stern Fund.

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  1. Department of Biology, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA

    L Guarente

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Guarente, L. Diverse and dynamic functions of the Sir silencing complex. Nat Genet 23, 281–285 (1999). https://doi.org/10.1038/15458

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