The Huntington's Disease Protein Interacts with p53 and CREB-Binding Protein and Represses Transcription

• Published in: Proceedings of the National Academy of Sciences - PNAS Vol. 97; no. 12; pp. 6763 - 6768
• Main Authors: Steffan, Joan S., Kazantsev, Aleksey, Spasic-Boskovic, Olivera, Greenwald, Marilee, Zhu, Ya-Zhen, Gohler, Heike, Wanker, Erich E., Bates, Gillian P., Housman, David E., Thompson, Leslie M.
• Format: Journal Article
• Language: English
• Published: United States National Academy of Sciences of the United States of America 06-06-2000; National Acad Sciences; National Academy of Sciences
• Subjects: Animals; Biological Sciences; Cell aggregates; Cell culture techniques; Cells, Cultured; CIP1 protein; CREB-binding protein; Cyclic AMP Response Element-Binding Protein - physiology; Disease; Exons; httex1 protein; Humans; Huntingtin Protein; Huntington disease; Huntington Disease - genetics; Inclusion bodies; MDR1 gene; Medical research; Mice; Mice, Inbred C57BL; Mice, Inbred CBA; Mice, Transgenic; mSin3a protein; Nerve Tissue Proteins - physiology; Neurodegenerative diseases; Neurological disorders; Nuclear inclusions; Nuclear Proteins - physiology; p21 protein; p21WAF1 protein; Proteins; Repression; Repressor Proteins - physiology; Transgenic animals; Tumor Suppressor Protein p53 - physiology; WAF-1 protein
• ISSN: 0027-8424; 1091-6490
• DOI: 10.1073/pnas.100110097

Huntington's Disease (HD) is caused by an expansion of a polyglutamine tract within the huntingtin (htt) protein. Pathogenesis in HD appears to include the cytoplasmic cleavage of htt and release of an amino-terminal fragment capable of nuclear localization. We have investigated potential consequences to nuclear function of a pathogenic amino-terminal region of htt (httex1p) including aggregation, protein-protein interactions, and transcription. httex1p was found to coaggregate with p53 in inclusions generated in cell culture and to interact with p53 in vitro and in cell culture. Expanded httex1p represses transcription of the p53-regulated promoters, p21WAF1/CIP1and MDR-1. httex1p was also found to interact in vitro with CREB-binding protein (CBP) and mSin3a, and CBP to localize to neuronal intranuclear inclusions in a transgenic mouse model of HD. These results raise the possibility that expanded repeat htt causes aberrant transcriptional regulation through its interaction with cellular transcription factors which may result in neuronal dysfunction and cell death in HD.