Sequence organization and matrix attachment regions of the human serine protease inhibitor gene cluster at 14q32.1.

The human serine protease inhibitor (serpin) gene cluster at 14q32.1 is a useful model system for studying the regulation of gene activity and chromatin structure. We demonstrated previously that the six known serpin genes in this region were organized into two subclusters of three genes each that occupied approximately 370 kb of DNA. To more fully understand the genomic organization of this region, we annotated a 1-Mb sequence contig from data from the Genoscope sequencing consortium (http://www.genoscope.cns.fr/ ). We report that 11 different serpin genes reside within the 14q32.1 cluster, including two novel alpha1-antiproteinase-like gene sequences, a kallistatin-like sequence, and two recently identified serpins that had not been mapped previously to 14q32.1. The genomic regions proximal and distal to the serpin cluster contain a variety of unrelated gene sequences of diverse function. To gain insight into the chromatin organization of the region, sequences with putative nuclear matrix-binding potential were identified by using the MAR-Wiz algorithm, and these MAR-Wiz candidate sequences were tested for nuclear matrix-binding activity in vitro. Several differences between the MAR-Wiz predictions and the results of biochemical tests were observed. The genomic organization of the serpin gene cluster is discussed.