Structure of the coiled-coil dimerization motif of Sir4 and its interaction with Sir3

Ju Fang Chang, Brian E. Hall, Jason C. Tanny, Danesh Moazed, David Filman, Tom Ellenberger

Research output: Contribution to journalArticlepeer-review

58 Scopus citations

Abstract

The yeast silent information regulators Sir2, Sir3, and Sir4 physically interact with one another to establish a transcriptionally silent state by forming repressive chromatin structures. The Sir4 protein contains binding sites for both Sir2 and Sir3, and these protein-protein interactions are required for gene silencing. Here, we report the X-ray structure of the coiled-coil dimerization motif within the C-terminus of Sir4 and show that it forms a stable 1:1 complex with a dimeric fragment of Sir3 (residues 464-978). We have identified a cluster of residues on the surface of the Sir4 coiled coil required for specific interactions with Sir3. The histone deacetylase Sir2 can also bind to this complex, forming a ternary complex with the truncated Sir3 and Sir4 proteins. The dual interactions of Sir4 with Sir3 and Sir2 suggest a physical basis for recruiting Sir3 to chromatin by virtue of its interactions with Sir4 and with deacetylated histones in chromatin.

Original languageEnglish
Pages (from-to)637-649
Number of pages13
JournalStructure
Volume11
Issue number6
DOIs
StatePublished - Jun 2003

Fingerprint

Dive into the research topics of 'Structure of the coiled-coil dimerization motif of Sir4 and its interaction with Sir3'. Together they form a unique fingerprint.

Cite this