Biomaterial Database

Expression of cyclin D1 mRNA is not upregulated by Myc in rat fibroblasts. 1995

D L Solomon, and A Philipp, and H Land, and M Eilers

Imperial Cancer Research Fund, London, UK.

Conflicting results have been published regarding the regulation of cyclin D1 mRNA in rat fibroblasts expressing a hormone-regulated Myc protein, MycER. We confirm that activation of MycER with oestrogen rapidly induces cyclin D1 mRNA, even in the presence of cycloheximide. However, we show that this is an artefact resulting from an oestrogen-activated transcriptional activation domain in the oestrogen receptor part of the MycER chimaera. First, addition of 4-hydroxy-tamoxifen (4OHT), which does not activate this domain, allows association of MycER with Max and induces cell proliferation in serum-starved Rat-1-MycER cells without affecting cyclin D1 mRNA levels or the activity of D1 promoter-luciferase constructs. Second, Rat-1 cells expressing a mutant MycER with a hormone-binding domain that still binds 4OHT but no longer binds oestrogen, are driven into the cell cycle in response to 4OHT but fail to up-regulate cyclin D1 mRNA. Finally, Rat-1 cells in which wild-type human c-Myc expression can be induced, also progress into the cell cycle without increased D1 mRNA expression.

UI	MeSH Term	Description	Entries
D011960	Receptors, Estrogen	Cytoplasmic proteins that bind estrogens and migrate to the nucleus where they regulate DNA transcription. Evaluation of the state of estrogen receptors in breast cancer patients has become clinically important.	Estrogen Receptor,Estrogen Receptors,Estrogen Nuclear Receptor,Estrogen Receptor Type I,Estrogen Receptor Type II,Estrogen Receptors Type I,Estrogen Receptors Type II,Receptor, Estrogen Nuclear,Receptors, Estrogen, Type I,Receptors, Estrogen, Type II,Nuclear Receptor, Estrogen,Receptor, Estrogen
D011993	Recombinant Fusion Proteins	Recombinant proteins produced by the GENETIC TRANSLATION of fused genes formed by the combination of NUCLEIC ACID REGULATORY SEQUENCES of one or more genes with the protein coding sequences of one or more genes.	Fusion Proteins, Recombinant,Recombinant Chimeric Protein,Recombinant Fusion Protein,Recombinant Hybrid Protein,Chimeric Proteins, Recombinant,Hybrid Proteins, Recombinant,Recombinant Chimeric Proteins,Recombinant Hybrid Proteins,Chimeric Protein, Recombinant,Fusion Protein, Recombinant,Hybrid Protein, Recombinant,Protein, Recombinant Chimeric,Protein, Recombinant Fusion,Protein, Recombinant Hybrid,Proteins, Recombinant Chimeric,Proteins, Recombinant Fusion,Proteins, Recombinant Hybrid
D004965	Estrogen Antagonists	Compounds which inhibit or antagonize the action or biosynthesis of estrogenic compounds.	Estradiol Antagonists,Antagonists, Estradiol,Antagonists, Estrogen
D005347	Fibroblasts	Connective tissue cells which secrete an extracellular matrix rich in collagen and other macromolecules.	Fibroblast
D005434	Flow Cytometry	Technique using an instrument system for making, processing, and displaying one or more measurements on individual cells obtained from a cell suspension. Cells are usually stained with one or more fluorescent dyes specific to cell components of interest, e.g., DNA, and fluorescence of each cell is measured as it rapidly transverses the excitation beam (laser or mercury arc lamp). Fluorescence provides a quantitative measure of various biochemical and biophysical properties of the cell, as well as a basis for cell sorting. Other measurable optical parameters include light absorption and light scattering, the latter being applicable to the measurement of cell size, shape, density, granularity, and stain uptake.	Cytofluorometry, Flow,Cytometry, Flow,Flow Microfluorimetry,Fluorescence-Activated Cell Sorting,Microfluorometry, Flow,Cell Sorting, Fluorescence-Activated,Cell Sortings, Fluorescence-Activated,Cytofluorometries, Flow,Cytometries, Flow,Flow Cytofluorometries,Flow Cytofluorometry,Flow Cytometries,Flow Microfluorometries,Flow Microfluorometry,Fluorescence Activated Cell Sorting,Fluorescence-Activated Cell Sortings,Microfluorimetry, Flow,Microfluorometries, Flow,Sorting, Fluorescence-Activated Cell,Sortings, Fluorescence-Activated Cell
D005786	Gene Expression Regulation	Any of the processes by which nuclear, cytoplasmic, or intercellular factors influence the differential control (induction or repression) of gene action at the level of transcription or translation.	Gene Action Regulation,Regulation of Gene Expression,Expression Regulation, Gene,Regulation, Gene Action,Regulation, Gene Expression
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D012333	RNA, Messenger	RNA sequences that serve as templates for protein synthesis. Bacterial mRNAs are generally primary transcripts in that they do not require post-transcriptional processing. Eukaryotic mRNA is synthesized in the nucleus and must be exported to the cytoplasm for translation. Most eukaryotic mRNAs have a sequence of polyadenylic acid at the 3' end, referred to as the poly(A) tail. The function of this tail is not known for certain, but it may play a role in the export of mature mRNA from the nucleus as well as in helping stabilize some mRNA molecules by retarding their degradation in the cytoplasm.	Messenger RNA,Messenger RNA, Polyadenylated,Poly(A) Tail,Poly(A)+ RNA,Poly(A)+ mRNA,RNA, Messenger, Polyadenylated,RNA, Polyadenylated,mRNA,mRNA, Non-Polyadenylated,mRNA, Polyadenylated,Non-Polyadenylated mRNA,Poly(A) RNA,Polyadenylated mRNA,Non Polyadenylated mRNA,Polyadenylated Messenger RNA,Polyadenylated RNA,RNA, Polyadenylated Messenger,mRNA, Non Polyadenylated
D013629	Tamoxifen	One of the SELECTIVE ESTROGEN RECEPTOR MODULATORS with tissue-specific activities. Tamoxifen acts as an anti-estrogen (inhibiting agent) in the mammary tissue, but as an estrogen (stimulating agent) in cholesterol metabolism, bone density, and cell proliferation in the ENDOMETRIUM.	ICI-46,474,ICI-46474,ICI-47699,Nolvadex,Novaldex,Soltamox,Tamoxifen Citrate,Tomaxithen,Zitazonium,Citrate, Tamoxifen,ICI 46,474,ICI 46474,ICI 47699,ICI46,474,ICI46474,ICI47699