Identification of genes encoding zinc finger motifs in the cardiovascular system.

The Zn2+-finger DNA-binding domain has been identified in several developmental control proteins, transcription factors and gene products associated with diseases, as well as in several RNA-binding proteins. We applied library screening, expressed sequence tagging (EST sequencing), Zn2+-binding assays and Northern blot hybridization, in order to characterize novel cDNA clones of the human cardiovascular system which contain Zn2+-finger motifs. An embryonic (8-10 weeks gestation) heart lambda ZAP Express cDNA library was screened with an oligonucleotide probe deduced from a consensus amino acid sequence which is highly conserved for Zn2+-finger proteins, and approximately 350 positive clones were isolated from 1 x 10(4) plaque-forming units (pfu) initially plated. The isolated clones were classified as known and novel following single pass automated DNA sequencing. Analysis of Northern blot hybridization delineated the tissue specificity of these clones, as well as their association with cardiac growth and development. Existence of Zn2+-finger motifs in the novel clones was confirmed by Zn2+-binding assay. In this report, we present the characterization of eight novel clones, including the complete cDNA sequences of one of these clones (HHZ-123).