1. Academic Validation
  2. Cloning, functional characterization, and mechanism of action of the B-cell-specific transcriptional coactivator OCA-B

Cloning, functional characterization, and mechanism of action of the B-cell-specific transcriptional coactivator OCA-B

  • Mol Cell Biol. 1995 Aug;15(8):4115-24. doi: 10.1128/MCB.15.8.4115.
Y Luo 1 R G Roeder
Affiliations

Affiliation

  • 1 Laboratory of Biochemistry and Molecular Biology, Rockefeller University, New York, New York 10021, USA.
Abstract

Biochemical purification and cognate cDNA cloning studies have revealed that the previously described transcriptional coactivator OCA-B consists of a 34- or 35-kDa polypeptide with sequence relationships to known coactivators that function by protein-protein interactions. Studies with a recombinant protein have proved that a single OCA-B polypeptide is the main determinant for B-cell-specific activation of immunoglobulin (Ig) promoters and provided additional insights into its mechanism of action. Recombinant OCA-B can function equally well with Oct-1 or Oct-2 on an Ig promoter, but while corresponding POU domains are sufficient for OCA-B interaction, and for octamer-mediated transcription of a histone H2B promoter, an additional Oct-1 or Oct-2 activation domain(s) is necessary for functional synergy with OCA-B. Further studies additional Oct-1 or Oct-2 activation domain(s) is necessary for functional synergy with OCA-B. Further studies show that Ig promoter activation by Oct-1 and OCA-B requires still other general (USA-derived) cofactors and also provide indirect evidence that distinct Oct-interacting cofactors regulate H2B transcription.

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