B-Myc is preferentially expressed in hormonally-controlled tissues and inhibits cellular proliferation.
The myc family of genes plays an important role in several cellular processes including proliferation, apoptosis, differentiation, and transformation. B-myc, a relatively new and largely unstudied member of the myc family, encodes a protein that is highly homologous to the N-terminal transcriptional regulatory domain of c-Myc. Here, we show that high level B-myc expression is restricted to specific mouse tissues, primarily hormonally-controlled tissues, with the highest level of expression in the epididymis. We also report the identification of the endogenous B-Myc protein from mouse tissues. Like other Myc family proteins, B-Myc is a short-lived nuclear protein which is phosphorylated on residues Ser-60 and Ser-68. Rapid proteolysis of B-Myc occurs via the ubiquitin-proteasome pathway. Finally, we found that overexpression of B-Myc significantly slows the growth of Rat la fibroblasts and COS cells suggesting B-Myc functions as an inhibitor of cellular proliferation.
Gregory
M A
MA
Department of Cell Biology, Vanderbilt University School of Medicine, Nashville, Tennessee 37232-2175, USA.
Xiao
Q
Q
Cornwall
G A
GA
Lutterbach
B
B
Hann
S R
SR
D000311:Adrenal Glands / Q000378:metabolism; D000818:Animals; D001921:Brain / Q000378:metabolism; D019556:COS Cells; D002455:Cell Division / Q000235:genetics*; D002467:Cell Nucleus / Q000378:metabolism; D002522:Chlorocebus aethiops; D003546:Cysteine Endopeptidases / Q000378:metabolism; D018076:DNA, Complementary / Q000235:genetics; D004822:Epididymis / Q000378:metabolism*; D005260:Female; D005347:Fibroblasts; D005786:Gene Expression Regulation; D016259:Genes, myc; D006131:Growth Inhibitors / Q000096:biosynthesis / Q000235:genetics / Q000502:physiology; D006728:Hormones / Q000502:physiology*; D008297:Male; D008321:Mammary Glands, Animal / Q000378:metabolism; D051379:Mice; D009097:Multienzyme Complexes / Q000378:metabolism; D009419:Nerve Tissue Proteins / Q000096:biosynthesis / Q000235:genetics; D009928:Organ Specificity; D010053:Ovary / Q000378:metabolism; D010766:Phosphorylation; D010902:Pituitary Gland / Q000378:metabolism; D011467:Prostate / Q000378:metabolism; D046988:Proteasome Endopeptidase Complex; D011499:Protein Processing, Post-Translational; D017346:Protein Serine-Threonine Kinases / Q000502:physiology; D016271:Proto-Oncogene Proteins c-myc / Q000096:biosynthesis* / Q000235:genetics; D051381:Rats; D011993:Recombinant Fusion Proteins / Q000096:biosynthesis; D014162:Transfection; D014452:Ubiquitins / Q000378:metabolism; D014599:Uterus / Q000378:metabolism
D018076:DNA, Complementary; D006131:Growth Inhibitors; D006728:Hormones; D009097:Multienzyme Complexes; D009419:Nerve Tissue Proteins; D016271:Proto-Oncogene Proteins c-myc; D011993:Recombinant Fusion Proteins; D014452:Ubiquitins; D017346:Protein Serine-Threonine Kinases; D003546:Cysteine Endopeptidases; D046988:Proteasome Endopeptidase Complex