Movement of chromosome sites within interphase cells is critical for numerous pathways including RNA transcription and genome organization. Yet, a mechanism for reorganizing chromatin in response to these events had not been reported. Here, we delineate a molecular chaperone dependent pathway for relocating activated gene loci in yeast. Our presented data support a model in which a two-authentication system mobilizes a gene promoter through a dynamic network of polymeric nuclear actin.

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... tion factor-dependent nucleation of a myosin motor propels the gene locus through the actin matrix and fidelity of the actin association was ensured by ARP-containing chromatin remodelers. Motor activity of nuclear myosin was dependent on the Hsp90 chaperone. Hsp90 further contributed by biasing the remodeler-actin interaction towards nucleosomes with the non-canonical histone H2A.Z thereby focusing the pathway on select sites such as transcriptionally active genes. Together, the system provides a rapid and effective means to broadly yet selectively mobilize chromatin sites.