Accession Number : ADA314259

Title :   Structure-Function Analysis of the v-Myc Oncoprotein.

Descriptive Note : Annual rept. 9 May 95-8 May 96,

Corporate Author : PURDUE RESEARCH FOUNDATION LAFAYETTE IN

Personal Author(s) : Taparowsky, Elizabeth J. ; Echlin, Deborah

PDF Url : ADA314259

Report Date : JUN 1996

Pagination or Media Count : 19

Abstract : The amino terminus of the Myc oncoprotein is important for many of the biological activities of the protein including transcriptional activation and repression, cellular transformation, and apoptosis. The amino terminus of Myc also contains highly conserved domains necessary for these varied functions of the oncoprotein. A yeast two-hybrid screen of a human cDNA library performed in our lab has yielded a novel factor that interacts with one of these conserved domains, Myc Homology Region II (MHR II). Analysis of this novel protein to discern potential effects on Myc function has yielded interesting results. Since MHR II is required by Myc to bring about cellular transformation, the effect of this clone on activated H-ras transformation was assessed. C3H10T1/2 fibioblasts were stably transfected with both activated human H-ras and the MHR II-associating pmtein, and focus formation was determined. The novel factor appears to be able to cooperate with H-ras to transform this cultured cell line. Another surprising potential effect on Myc function is its apparent ability to repress the transcriptional activity of Myc. Transient transfections in C3H10OT1/2 cells utilizing the GAL4 reporter system and various deletion mutants of the v-Myc amino terminus have initially implicated the novel protein as a general repressor of transcription, since it not only suppresses Myc transactivation but also that of the potent activator vP16. Further analysis to assess what contribution this new factor has on Myc's other functions is underway.

Descriptors :   *PROTEINS, *DEOXYRIBONUCLEIC ACIDS, *CARBOXYLIC ACIDS, BIOLOGY, CELLS, AMINES, GENES, FIBROBLASTS, AMINO ACIDS, TRANSFORMATIONS, HELIXES, MYCOLOGY, ONCOGENIC VIRUSES.

Subject Categories : Biochemistry

Distribution Statement : APPROVED FOR PUBLIC RELEASE