Abstract
C′BP-1, a protein that binds to the MRE-c′ region (-135 to -110) of the mouse metallothionein-I (MT-I) gene in metal-independent manner, was purified from rat liver nuclear extract by ion exchange and affinity chromatography. Analysis by SDS–PAGE, UV crosslinking, and glycerol gradient sedimentation, taken together, showed that C′BP-1 is a dimer of the 34-kDa polypeptides. Affinity-purified C′BP-1 could significantly stimulate transcription from mouse MT-I gene promoter. DNase I footprinting with the purified protein identified two binding sites for C′BP-1 located at positions -135 to -100 and -210 to -175 with respect to the start site of MT-I gene transcription. Both C′BP-1 binding sequences were found to contain imperfect dyad of the CCAAT homology. C′BP-1 was shown to make critical contacts with the CCAAT homology by methylation interference analysis and competition electrophoretic mobility shift assay with mutants harboring alterations in the CCAAT homology. An antibody that specifically recognizes C/EBPδ partially supershifted C′BP-1/MRE-c′ complex, suggesting that C′BP-1 is identical to C/EBPδ or is closely related to C/EBPδ.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
