Analysis of the mechanism regulating the stability of rat macrophage inflammatory protein‐2 mRNA in RBL‐2H3 cells

Abstract

Using rat peritoneal neutrophils, the complete nucleotide sequence of rat macrophage inflammatory protein-2 (MIP-2) mRNA including 5'untranslated region (UTR) and 3'UTR was determined (GenBank Accession number, AB060092). It was found that the MIP-2 mRNA has a 70 bp 5'UTR, a 303 bp coding region and a 728 bp 3'UTR which contains adenylate/uridylate (AU)-rich areas defined as AU-rich elements (AREs). Site-directed mutagenesis studies using the tetracycline-sensitive transactivator protein-expressing rat basophilic leukemia cells (RBL-2H3-TO cells) revealed that MIP-2 mRNA mutants which lack the 3'UTR are more stable than MIP-2-wild-type (wt) mRNA. A MIP-2 mRNA mutant in which some mutations were introduced to the ARE was also stable. The stability of MIP-2 mRNA was low in untreated RBL-2H3-TO cells, but it increased in the antigen-stimulated immunoglobulin E (IgE)-sensitized cells. The antigen-induced MIP-2 mRNA stabilization was counteracted by the highly specific p38 mitogen-activated protein kinase (MAPK) inhibitor SB203580 and the MAPK/ERK kinase (MEK-1) inhibitor PD98059. These findings indicate that ARE is the cis-element which mediates the rapid decay of MIP-2 mRNA, and the antigen stimulation stabilizes MIP-2 mRNA and the p38 MAPK and p44/42 MAPK pathways are involved in the antigen-induced stabilization of MIP-2 mRNA.

PARP1 promotes gene expression at the post-transcriptional level by modulating the RNA-binding protein HuR

“…In parallel experiments, the firefly luciferase mRNA level was significantly decreased (to ∼3%) (Fig. 1f), indicating the Cxcl2 -3′-UTR was indeed a destabilizing determinant21. LPS stimulation did not affect the activity or the mRNA level of firefly luciferase in cells transfected with the pGL3-control, where the luciferase gene was constitutively transcribed.…”

Activation of ETB receptors regulates the abundance of ET‐1 mRNA in vascular endothelial cells

“…The ERK and p38 MAPK pathways have been implicated in regulating gene expression ( Edmunds and Mahadevan, 2004 ) and mRNA stability ( Kotlyarov and Gaestel, 2002 ; Numahata et al , 2003 ; Chrestensen et al , 2004 ). Hence, we sought to determine if activation of ET B receptors induced activation of either the ERK or p38 MAPK pathway with a time course similar to the reduction in ET‐1 mRNA levels.…”

Inflammatory Stress and Idiosyncratic Hepatotoxicity: Hints from Animal Models

“…Many of the cytokines/chemokines that are selectively up-regulated in LPS/RAN-treated rats (Luyendyk et al, 2006b;Tukov et al, 2007) are regulated by p38 and its downstream MAPK-activated protein kinase-2 (Neininger et al, 2002;Numahata et al, 2003;Hitti et al, 2006). Thus, it seemed possible that p38 MAPK activation might be an upstream signal leading to the pathogenic cascade.…”