POU-domain proteins Pit-1 and Oct-1 interact to form a heteromeric complex and can cooperate to induce expression of the prolactin promoter

• Published in: Genes & development Vol. 5; no. 7; pp. 1309 - 1320
• Main Authors: VOSS, J. W, WILSON, L, ROSENFELD, M. G
• Format: Journal Article
• Language: English
• Published: Cold Spring Harbor, NY Cold Spring Harbor Laboratory 01.07.1991
• Subjects: Animals; Base Sequence; Biological and medical sciences; Cell Line; Cercopithecus aethiops; DNA-Binding Proteins - genetics; Enhancer Elements, Genetic; Fundamental and applied biological sciences. Psychology; Gene Expression Regulation; Host Cell Factor C1; Kidney; Macromolecular Substances; Molecular and cellular biology; Molecular genetics; Molecular Sequence Data; Octamer Transcription Factor-1; Pituitary Gland, Anterior; Prolactin - genetics; Prolactin - metabolism; Promoter Regions, Genetic; Protein Conformation; Transcription Factor Pit-1; Transcription Factors - genetics; Transcription. Transcription factor. Splicing. Rna processing; Transcriptional Activation; Rat; Transcription; Transcription promoter; Rodentia; Tissue specificity; Molecular interaction; Activation; Gel retardation technique; Synergism; Vertebrata; Mammalia; Gene; Prolactin; Pituitary gland; Transcription factor
• ISSN: 0890-9369; 1549-5477
• DOI: 10.1101/gad.5.7.1309

Two members of the POU-domain family of transcriptional activators, Pit-1 and Oct-1, are coexpressed in cells of the anterior pituitary gland. We demonstrate that the pituitary-specific developmental regulator Pit-1 can bind as a heterodimer with the widely expressed 100-kD Oct-1 protein to critical tissue-specific cis-active elements in the rat prolactin gene. Pit-1 and Oct-1 can also associate, in the absence of DNA, via their POU domains. Coexpression of Pit-1 and Oct-1 in a heterologous cell type results in reproducible 2- to 2.5-fold synergistic transcriptional effects on genes under control of the native prolactin promoter or of a single Pit-1 response element. These results suggest that a combinatorial pattern of heterodimeric and homodimeric interactions between different members of the POU-domain gene family can result when members of this large family are coexpressed in cells of developing and established organ systems, potentially regulating differential developmental gene activation.