Molecular cloning and characterization of a human homologue of TBPIP, a BRCA1 locus-related gene.
Here we clone the human homologue of TBPIP [Tat binding protein 1(TBP-1)-interacting protein]. TBPIP is a molecule that has been cloned from mouse as a cofactor of TBP-1. Eighty-eight per cent of the deduced amino acid sequence of human TBPIP coincides with that of mouse TBPIP. CAT assay reveals that human TBPIP could interact with human TBP-1, then enhance the function of TBP-1 on HIV (human immunodeficiency virus)-Tat-mediated transactivation. Our radiation hybrid mapping indicates that TBPIP is located on chromosome 17q12-21. A DNA database search uncovers that an apparent part of TBPIP has been obtained as a BRCA1 locus-related gene (OV-4) and mapped onto chromosome 17q12-21. Interestingly, the nucleotide structure of human TBPIP is very similar to that of the GT198 gene, which has been cloned from a human breast cancer cell line and also mapped onto the BRCA1 locus. Since a very high rate of gene mutation is observed in the BRCA1-related region in breast cancers and expression of authentic GT198 mRNA could not be confirmed in either BT-474 (other kind of human breast cancer cell line) or normal human testis (where the strong expression of GT198 mRNA is reported), it is likely that GT198 is a mutated form of human TBPIP.
Ijichi
H
H
First Department of Anatomy, Osaka City University Medical School, 1-4-3 Asahimachi, Abeno-ku, Osaka, Japan.
Tanaka
T
T
Nakamura
T
T
Yagi
H
H
Hakuba
A
A
Sato
M
M
D000074183:ATPases Associated with Diverse Cellular Activities; D000595:Amino Acid Sequence; D000818:Animals; D019313:BRCA1 Protein / Q000235:genetics*; D001483:Base Sequence; D016466:CHO Cells; D015500:Chloramphenicol O-Acetyltransferase / Q000235:genetics / Q000378:metabolism; D002874:Chromosome Mapping; D002886:Chromosomes, Human, Pair 17 / Q000235:genetics; D003001:Cloning, Molecular; D006224:Cricetinae; D018076:DNA, Complementary / Q000737:chemistry / Q000235:genetics; D004274:DNA, Recombinant / Q000235:genetics; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism; D015696:Gene Products, tat / Q000235:genetics / Q000502:physiology; D006801:Humans; D006822:Hybrid Cells; D008297:Male; D008969:Molecular Sequence Data; D010957:Plasmids; D046988:Proteasome Endopeptidase Complex; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid; D012689:Sequence Homology, Nucleic Acid; D015533:Transcriptional Activation; D014407:Tumor Cells, Cultured
D019313:BRCA1 Protein; D018076:DNA, Complementary; D004274:DNA, Recombinant; D004268:DNA-Binding Proteins; D015696:Gene Products, tat; D011993:Recombinant Fusion Proteins; D015500:Chloramphenicol O-Acetyltransferase; D046988:Proteasome Endopeptidase Complex; D000074183:ATPases Associated with Diverse Cellular Activities; C064757:PSMC3 protein, human