Binding constant determination studies utilizing recombinant delta CREB protein.

J S Williams; J E Dixon; O M Andrisani

doi:10.1089/dna.1993.12.183

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Binding constant determination studies utilizing recombinant delta CREB protein.

J S Williams·J E Dixon·O M Andrisani

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Abstract

In this study, we report the binding constants (Kd) of the cAMP-responsive element binding protein (delta-CREB) for various cAMP-response element (CRE) motifs. We utilized purified recombinant delta CREB protein in binding reactions with natural CRE motifs found in the promoter of two neuropeptide hormone genes and with several variant CRE motifs. The Kd of delta CREB for the perfectly palindromic CRE, TGACG-TCA, found within the somatostatin promoter is estimated to be 5.0 x 10(-9) M. The Kd of delta CREB for the variant CRE motif TG_CGTCA found within the enkephalin promoter is calculated to be in the 3 x 10(-8) M. These studies provide an in vitro quantitative assessment of the binding affinity of delta CREB for various CRE motifs.

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Amino Acid Sequence Base Sequence Cyclic AMP Response Element-Binding Protein Kinetics Molecular Sequence Data Protein Binding Recombinant Proteins Regulatory Sequences, Nucleic Acid Journal Article Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, P.H.S.

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J S Williams, J E Dixon, O M Andrisani. 1993. Binding constant determination studies utilizing recombinant delta CREB protein.. https://doi.org/10.1089/dna.1993.12.183

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