| First Author | Cok SJ | Year | 2004 |
| Journal | J Biol Chem | Volume | 279 |
| Issue | 9 | Pages | 8196-205 |
| PubMed ID | 14662769 | Mgi Jnum | J:89038 |
| Mgi Id | MGI:3037670 | Doi | 10.1074/jbc.M308475200 |
| Citation | Cok SJ, et al. (2004) Identification of RNA-binding proteins in RAW 264.7 cells that recognize a lipopolysaccharide-responsive element in the 3-untranslated region of the murine cyclooxygenase-2 mRNA. J Biol Chem 279(9):8196-205 |
| abstractText | RAW 264.7 cells rapidly induce cyclooxygenase-2 (COX-2) in response to lipopolysaccharide treatment. Part of the increased COX-2 expression occurred through post-transcriptional mechanisms mediated through specific regions of the 3'-untranslated region (UTR) of the message. The proximal region of the 3'-UTR of COX-2 contains a highly conserved AU-rich element that was able to confer lipopolysaccharide regulation of a chimeric reporter-gene. Electrophoretic mobility shift assays demonstrated that the RNA-binding proteins TIAR, AUF1, HuR, and TIA-1 all form an RNA-protein complex with the first 60 nucleotides of the 3'-UTR of COX-2. Biotinylated RNA probes were used to isolate additional proteins that bind the 3'-UTR of COX-2. We identified several RNA-binding proteins including TIAR, AUF1, CBF-A, RBM3, heterogeneous nuclear ribonucleoprotein (hnRNP) A3, and hnRNP A2/B1. We identified four alternatively spliced isoforms of AUF1 which migrated at multiple isoelectric points. Likewise, we identified alternatively spliced isoforms of CBF-A, hnRNP A3, and hnRNP A2/B1. Western analysis of two-dimensional gels identified multiple isoforms of TIA-1, TIAR, and AUF1 at pI values that spanned nearly 3 pH units. Thus, through a combination of alternative splicing and post-translational modification cells are able to increase greatly the repertoire of protein species expressed at a given time or in response to extracellular stimuli. |
