Fig. 3.

Protein network analysis links SIRT7 to chromatin modification and remodeling complexes. Protein networks were assembled by STRING and visualized using Cytoscape. Genes without known functional connections were excluded and are presented in supplemental Fig. S7. Node color and size represent relative protein abundance (NSAF) within SIRT7 immunoisolates that were normalized by overall human proteome abundance (PAX). Both NSAF and PAX abundance values are calculated from mass spectrometric spectral counting data (see “Experimental Procedures”). A, protein network assembled by STRING from genes with chromatin modification or chromatin remodeling biological process ontology terms (Fig. 2C, yellow circles, and supplemental Table S6). 26 of 33 genes (yellow colored nodes) were connected into a functional network. B, functional network representing 22 proteins that link SIRT7 to chromatin remodeling complexes via transcriptional regulation. STRING analysis was conducted on the subset of chromatin remodeling complex members from A, supplemented with previously known SIRT7 interactions and members of chromatin remodeling complexes that were also in the nuclear classification of SIRT7 immunoisolates (Fig. 2A and supplemental Table S7).