An A + U-rich element RNA-binding factor regulates c-myc mRNA stability in vitro.
Transient expression of some proto-oncogenes, cytokines, and transcription factors occurs as a cellular response to growth factors, 12-O-tetradecanoylphorbol-13-acetate, antigen stimulation, or inflammation. Expression of these genes is mediated in part by the rapid turnover of their mRNAs. A + U-rich elements in the 3' untranslated regions of these mRNAs serve as one recognition signal targeting the mRNAs for rapid degradation. I report the identification of a cytosolic factor that both binds to the proto-oncogene c-myc A + U-rich element and specifically destabilizes c-myc mRNA in a cell-free mRNA decay system which reconstitutes mRNA decay processes found in cells. Proteinase K treatment of the factor abolishes its c-myc mRNA degradation activity without affecting its RNA-binding capacity. Thus, RNA substrate binding and degradation appear to be separable functions. These findings should aid in understanding how the cell selectively targets mRNAs for rapid turnover.
Brewer
G
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Department of Microbiology and Immunology, Bowman Gray School of Medicine, Wake Forest University, Winston-Salem, North Carolina 27103.
D000225:Adenine; D002352:Carrier Proteins / Q000302:isolation & purification / Q000378:metabolism*; D002460:Cell Line; D002474:Cell-Free System; D003001:Cloning, Molecular; D003600:Cytosol / Q000378:metabolism; D016259:Genes, myc; D006801:Humans; D007700:Kinetics; D011485:Protein Binding; D000090063:Proto-Oncogene Mas; D012333:RNA, Messenger / Q000235:genetics* / Q000378:metabolism; D016601:RNA-Binding Proteins; D015183:Restriction Mapping; D014158:Transcription, Genetic; D014498:Uracil
D002352:Carrier Proteins; C000715470:MAS1 protein, human; D000090063:Proto-Oncogene Mas; D012333:RNA, Messenger; D016601:RNA-Binding Proteins; D014498:Uracil; D000225:Adenine