title: Isolation, differential splicing and protein expression of a DNase on the human X chromosome.
abstract: A systematic search for genes differentially expressed in human tissues resulted in the isolation of a gene encoding a protein with high homology to DNase I. In addition to the recently described cDNA sequence (Parrish et al., 1995) we have isolated a transcript, alternatively spliced in the 5' noncoding region. The gene is located between the QM and the XAP-2 gene in Xq28 and encodes a 302 amino acid protein with 39% identity to human DNase I. Besides a high homology at the nucleotide and amino acid level, most exon-intron boundaries of DNase I and DNase X are identical, indicating that both genes may have evolved from a common ancestor. The predicted function was verified by expression of a recombinant protein in an inducible bacterial system and detection of DNase activity. In contrast to DNase I a 18 kdal amino terminal fragment of the full length 35 kdal protein exhibited DNase activity.
authors.affiliation: Deutsches Krebsforschungszentrum, Abteilung Molekulare Genomanalyse, INF 280, Heidelberg, Germany.
authors.forename: J F
authors.initials: JF
authors.lastname: Coy
authors.forename: I
authors.initials: I
authors.lastname: Velhagen
authors.forename: R
authors.initials: R
authors.lastname: Himmele
authors.forename: H
authors.initials: H
authors.lastname: Delius
authors.forename: A
authors.initials: A
authors.lastname: Poustka
authors.forename: H
authors.initials: H
authors.lastname: Zentgraf