BINDING OF MATRIX ATTACHMENT REGIONS TO NUCLEAR LAMIN IS MEDIATED BY THE ROD DOMAIN AND DEPENDS ON THE LAMIN POLYMERIZATION STATE

The nuclear matrix maintains specific interactions with genomic DNA at sites known as matrix attachment regions (M/SARs). M/SARs bind in vit ro to lamin polymers. We show that the polymerized alpha-helical rod d omain of lamin Dm(0) provides by itself the specific binding to the ft z M/SAR. In contrast, unpolymerized rod domain does not bind specifica lly to this M/SAR, Non-specific binding to DNA is also observed with D m(0) containing a point mutation that impairs its ability to polymeriz e or with the isolated tail domain, These data suggests that the speci fic binding of lamins to M/SARs requires the rod domain and depends on the lamin polymerization state.