c-myc RNA degradation in growing and differentiating cells: Possible alternate pathways

Journal Article · Sun Jan 01 04:00:00 EST 1989 · Molecular and Cellular Biology; (USA)

DOI:https://doi.org/10.1128/MCB.9.1.288· OSTI ID:5518389

Swartwout, S G ^[1]; Kinniburgh, A J ^[2]

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1. Roswell Park Memorial Inst., Buffalo, NY (USA)
2. Roswell Park Memorial Inst., Buffalo, NY (USA). Dept. of Hematology Research

Transcripts of the proto-oncogene c-myc are composed of a rapidly degraded polyadenylated RNA species and an apparently much more stable, nonadenylated RNA species. In this report, the extended kinetics of c-myc RNA turnover have been examined in rapidly growing cells and in cells induced to differentiate. When transcription was blocked with actinomycin D in rapidly growing cells, poly(A)/sup +/ c-myc was rapidly degraded (t/sub 1/2/ = 12 min). c-myc RNA lacking poly (A) initially remained at or near control levels; however, after 80 to 90 min it was degraded with kinetics similar to those of poly (A)/sup +/ c-myc RNA. These bizarre kinetics are due to the deadenylation of poly (A)/sup +/ c-myc RNA to form poly (A)/sup -/ c-myc, thereby initially maintaining the poly (A)/sup -/ c-myc RNA pool when transcription is blocked. In contrast to growing cells, cells induced to differentiate degraded both poly (A)/sup +/ and poly (A)/sup -/ c-myc RNA rapidly. The rapid disappearance of both RNA species in differentiating cells suggests that a large proportion of the poly (A)/sup +/ c-myc RNA was directly degraded without first being converted to poly (A)/sup -/ c-myc RNA. Others have shown that transcriptional elongation of the c-myc gene is rapidly blocked in differentiating cells. The authors therefore hypothesize that in differentiating cells a direct, rapid degradation of poly (A)/sup +/ c-myc RNA may act as a backup or fail-safe system to ensure that c-myc protein is not synthesized.

• OSTI ID: 5518389
• Journal Information: Molecular and Cellular Biology; (USA), Journal Name: Molecular and Cellular Biology; (USA) Vol. 9:1; ISSN MCEBD; ISSN 0270-7306
• Country of Publication: United States
• Language: English

Related Subjects

550200* -- Biochemistry
550400 -- Genetics
59 BASIC BIOLOGICAL SCIENCES
BIOCHEMICAL REACTION KINETICS
BIOLOGICAL FUNCTIONS
BIOLOGICAL PATHWAYS
CELL DIFFERENTIATION
CELL PROLIFERATION
FUNCTIONS
GENE REGULATION
GENES
KINETICS
MOLECULAR BIOLOGY
NUCLEIC ACIDS
ONCOGENES
ORGANIC COMPOUNDS
PHENOTYPE
REACTION KINETICS
RNA
TRANSCRIPTION