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Ig/EBP (C/EBP gamma) is a transdominant negative inhibitor of C/EBP family transcriptional activators.

ABSTRACT: Analysis of cDNA and genomic clones shows that the murine Ig/EBP (C/EBP gamma) gene encodes a small protein with a predicted molecular weight of 16.4 kDa which contains C/EBP family basic and leucine zipper domains but lacks the transcriptional activation domains present in C/EBP (C/EBP alpha) and NF-IL6 (C/EBP beta). In transfection assays Ig/EBP is neither an activator nor a repressor of transcription; however, Ig/EBP inhibits the transcriptional ability of NF-IL6 (C/EBP beta) and C/EBP (C/EBP alpha), acting as a transdominant negative regulator. Thus Ig/EBP resembles LIP, another negative regulator of the C/EBP family, in both structure and transcriptional activity. Of the three known C/EBP family inhibitors, Ig/EBP, LIP and CHOP-10, only Ig/EBP is ubiquitously expressed. Therefore, Ig/EBP may act as a general buffer for C/EBP activators in many cell types.

SUBMITTER: Cooper C

PROVIDER: S-EPMC307392 | biostudies-other | 1995 Nov

REPOSITORIES: biostudies-other

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Ig/EBP (C/EBP gamma) is a transdominant negative inhibitor of C/EBP family transcriptional activators.

Cooper C C Henderson A A Artandi S S Avitahl N N Calame K K

Nucleic acids research 19951101 21

Analysis of cDNA and genomic clones shows that the murine Ig/EBP (C/EBP gamma) gene encodes a small protein with a predicted molecular weight of 16.4 kDa which contains C/EBP family basic and leucine zipper domains but lacks the transcriptional activation domains present in C/EBP (C/EBP alpha) and NF-IL6 (C/EBP beta). In transfection assays Ig/EBP is neither an activator nor a repressor of transcription; however, Ig/EBP inhibits the transcriptional ability of NF-IL6 (C/EBP beta) and C/EBP (C/EBP ...[more]

PMID: 7501458

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