Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P04626 (erbB-2)
 5,251 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Enhancer factor I (EFI) is a trans-acting factor which binds to the Rous sarcoma virus long terminal repeat enhancer and promoter at two inverted CCAAT-box motifs. We demonstrate that two forms of EFI DNA binding activity exist in nuclear extracts of avian cells. One form requires two heterologous components (EFIA)(EFIB) for high affinity, specific DNA binding activity, whereas a second form is not dependent on EFIB for binding and may be composed solely of EFIA, perhaps as a multimer. Both forms give rise to the same mobility shift in gel retardation assays, but the two forms can be separated chromatographically under buffer conditions which stabilize the two DNA binding activities. A cDNA for EFIA has been isolated from a rat liver cDNA expression library. The 1489-base pair EFIA cDNA encodes a 322-amino acid protein which is nearly identical to two previously described human DNA binding proteins. These are dbpB, a DNA binding protein of unknown specificity which binds to the epidermal growth factor receptor enhancer and c-erbB-2 gene promoter (Sakura, H., Maekawa, T., Imamoto, F., Yasuda, K., and Ishii, S. (1988) Gene (Amst.) 73, 499-507), and YB-1, a protein which recognizes the Y-box (inverted CCAAT motif) of the HLA-DR alpha chain gene (Didier, D. K., Schiffenbauer, J., Woulfe, S. L., Zacheis, M., and Schwartz, B. D. (1988) Proc. Natl. Acad. Sci. U. S. A. 85, 7322-7326). EFIA/dbpB/YB-1 share a highly conserved region of 100 amino acids with dbpA, another protein identified by Sakura et al. (1988) which binds to the epidermal growth factor receptor enhancer and c-erbB-2 gene promoter, and with two Xenopus CCAAT binding proteins, FRG Y1 and FRG Y2 (Tafuri, S. R., and Wolffe, A. P. (1990) Proc. Natl. Acad. Sci. U. S. A., in press). This highly conserved domain among all six proteins is presumed to represent or contain a DNA binding domain for the CCAAT motif. In addition, we note that the EFIA/dbpB/YB-1 polypeptide contains a novel arrangement of alternating clusters of positively and negatively charged amino acids not yet reported for any trans-acting factor. The functional significance of this novel structural motif, which is also conserved in dbpA, FRG Y1, and FRG Y2, will be discussed.
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PMID:Isolation and characterization of a cDNA clone for the CCAAT transcription factor EFIA reveals a novel structural motif. 196 30

Two cDNAs encoding new DNA-binding proteins (Dbps) have been cloned using a human placenta lambda gt11 recombinant cDNA library and DNA fragments as probes. Hybrid proteins expressed by the lambda gt11 cDNA library were blotted onto nitrocellulose filters, and incubated with three different radio-labeled DNA probes containing the human epidermal growth factor (EGF) receptor enhancer or the human c-erbB-2 promoter. Two kinds of clones, named dbpA and dbpB, showed high affinities for the DNA probes. The comparison of the nucleotide and the deduced amino acid (aa) sequences between these two cDNAs indicated that 100 of 109 aa located in the central region of these two Dbps were identical. The dbpA and dbpB-coded proteins also had an affinity for other cDNA probes such as the human c-ski gene, but not for poly(dI-dC).poly(dI-dC), suggesting that the sequence(s) recognized by the dbpA and dbpB-coded proteins may occur frequently, or that these proteins bind to DNA non-specifically in a different manner from that of histones. A simple method, described in this paper, can be used to isolate cDNA clones encoding Dbps. Strategies used for the detection of sequence-specific and non-specific Dbps are discussed.
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PMID:Two human genes isolated by a novel method encode DNA-binding proteins containing a common region of homology. 297 58