Analysis of the chicken DNA fragments that contain structural sites of attachment to the nuclear matrix: DNA-matrix interactions and replication.

Ten short DNA fragments have been selected from a library of the nuclear matrix-attached DNA (nmDNA) from chicken erythrocytes by their ability to hybridize with the fraction of chicken replication origins isolated by nascent DNA strand extrusion. The primary structure of these fragments has been determined. Five of the sequences contained a topoisomerase II recognition site. Most of the studied DNA fragments also have a common eight-nucleotide motif, GCAGACCG/A. A sequence-specific DNA-binding protein with a MW of 55 kDa that interacted with this motif has been identified. Some of the cloned DNA fragments promoted an increased level of transient plasmid replication in transfected chicken cells. The ability of plasmid bearing nmDNA fragments to replicate correlated directly with their ability to target plasmids to the nuclear matrix compartment.