A complete cDNA encoding the acrosin-trypsin inhibitor, HUSI-II, was used as a probe to isolate genomic clones from a human placenta library. Three clones which cover the entire HUSI-II gene were isolated and characterized. The exon-intron organization of the gene was determined and found to be identical to other known Kazal-type inhibitor-encoding genes. The striking similarity in the amino acid sequences which was found previously in HUSI-II and glycoprotein hormone β-subunits, is neither reflected in codon usage nor in the exon-intron arrangement of the genes. A 1.8-kb segment 5′ of the gene was sequenced. The analysis of this sequence showed that HUSI-II contains a G + C-rich region upstream from the transcription start point (tsp) which fulfills the criteria for a CpG island. Furthermore, in the first intron, a potential glucocorticoid-responsive element was found as a half-palindrome flanked by two CACCC elements. Determination of the tsp by S1 mapping revealed that HUSI-II has multiple tsp. Genomic Southern hybridization was used to show that HUSI-II is a single-copy gene. The localization of the gene to chromosome 4 was determined by hybridization of a 5′ genomic fragment to the DNA of a panel of somatic hybrids between human and rodent cells. © 1993.
Moritz, A., Grzeschik, K. H., Wingender, E., & Fink, E. (1993). Organization and sequence of the gene encoding the human acrosin-trypsin inhibitor (HUSI-II). Gene, 123(2), 277–281. https://doi.org/10.1016/0378-1119(93)90138-S