The human transferrin gene: 5' region contains conserved sequences which match the control elements regulated by heavy metals, glucocorticoids and acute phase reaction

Transferrin is a major plasma protein that transports iron to proliferating cells throughout the body. A clone containing the 5' region of the human transferrin gene has been isolated and characterized. A 14 kb EcoRI fragment was identified that contained the first 8 exons of the transferrin gene and 3.6 kb of its 5' flanking region. Conserved sequences identical or homologous to regulatory elements responding to heavy metals, glucocorticoid receptor and a putative acute phase reaction signal were identified in the 5'flanking region and intron 1. Also, the regulatory region of the transferrin gene contains a 14-bp sequence which closely matches sequences found in the interleukin-2 and gamma-interferon genes. All three genes are expressed by T lymphocytes before proliferation. A secondary loop structure similar to that proposed for the ovotransferrin gene can be formed by sequences in the 5' untranslated region of the transferrin mRNA.     

Molecular cloning and sequence of the gene for p9Ka. A cultured myoepithelial cell protein with strong homology to S-100, a calcium-binding protein

The gene for p9Ka, a protein of molecular weight 9000 that is expressed in cultured rat mammary myoepithelial cells, has been isolated from a normal rat genomic library in bacteriophage lambda, by its ability to hybridize to a cloned complementary DNA corresponding to p9Ka mRNA. The cloned rat genomic DNA fragment hybridized to translatable p9Ka mRNA. A nucleotide sequence of 2340 base-pairs of genomic DNA surrounding the p9Ka cDNA sequence has been obtained; the gene contains one intervening sequence of 675 nucleotides. The 3' end of the p9Ka mRNA has been identified on the gene sequence to be 13 nucleotides downstream from a poly(A) addition signal AATAAA. The gene contains an open reading frame of 101 amino acid residues, which is the only open reading frame in the entire gene long enough to encode a protein of molecular weight at least 9000. This hypothetical protein sequence shows greater than 40% homology to rat or bovine S-100 protein and over 30% homology to bovine intestinal calcium-binding protein. The results suggest that p9Ka may be related to a family of low molecular weight calcium-binding proteins.