| First Author | Berberich SJ | Year | 1999 |
| Journal | Differentiation | Volume | 64 |
| Issue | 4 | Pages | 205-12 |
| PubMed ID | 10365438 | Mgi Jnum | J:55449 |
| Mgi Id | MGI:1338135 | Doi | 10.1046/j.1432-0436.1999.6440205.x |
| Citation | Berberich SJ, et al. (1999) mdm-2 gene amplification in 3T3-L1 preadipocytes. Differentiation 64(4):205-12 |
| abstractText | In this study the regulation of the murine double minute-2 (mdm-2) gene was examined in NIH 3T3-L1 preadipocytes. The 3T3-L1 cell line, under proper conditions, has the capacity to differentiate from fibroblasts into adipocytes [15]. A recent report demonstrated that mdm-2 overexpression could block myogenesis [12]. While examining the regulation of the mdm-2 gene during adipogenesis, it was discovered that 3T3-L1 cells possess a 36-fold elevation of mdm-2 mRNA relative to A31 cells, another immortalized Balb/c 3T3 fibroblast cell line that lacks the capacity to differentiate. Based on Southern blot analysis, the increase in mdm-2 mRNA was the result of a mdm-2 gene amplification. The level of Mdm-2 protein in undifferentiated 3T3-L1 cells was elevated relative to A31 fibroblasts and resulted from translation of mRNA transcripts initiating from the p53-independent P1 promoter. We also examined how mdm-2 and p53 levels changed as undifferentiated fibroblasts converted to adipocytes. While mdm-2 mRNA levels remained elevated, p53 mRNA, protein, and DNA-binding activity decreased. These results suggest that adipogenesis is unaffected by elevated Mdm-2 levels and that the overexpression of mdm-2 mRNA is predominantly p53 independent. |
