KH‐type splicing regulatory protein mediate inflammatory response in gastric epithelial cells induced by lipopolysaccharide

Abstract

To study differential expressions of KH-type splicing regulatory protein (KSRP) and inflammatory factors and to explore the relationship between them in Lipopolysaccharide (LPS)-induced gastric epithelial cells (GES-1), cells were exposed to LPS for 24 h in the presence or absence of SC-514. Western blot and real-time PCR (RT-PCR) were used to analysis the contents of KSRP, inducible NO synthase (iNOS) and cyclooxygenase-2 (COX-2). The results showed that LPS decreased the expression of KSRP protein in GES-1 cells, but not KSRP mRNA, while increasing the levels of iNOS and COX-2 proteins and mRNAs in GES-1cells. High expression of KSRP induced low expressions and stabilities of iNOS and COX-2 in GES-1 cells, indicated that KSRP protein presented negative correlation with iNOS and COX-2 with LPS stimulation. In conclusion, the regulation of expression of KSRP was mainly achieved through post-translational modification. KSRP protein participated in regulating the expression of iNOS and COX-2 in their transcription and translation levels. In response to LPS or gram negative pathogenic microorganism, KSRP could regulate Toll-like receptor (TLR)/ Nuclear factor-kappa B (NF-κB) signal pathway in GES-1 cells.

LncRNA HOTAIR regulates lipopolysaccharide-induced cytokine expression and inflammatory response in macrophages

“…Briefly, RAW264.7 cells were treated with IKKβ-inhibitor SC-514 (25 µM, 1 h) and stimulated with LPS. The concentration of the inhibitor (SC-514) used is chosen based on previous literature 68 . Proteins from the control and SC-514 treated cells were analyzed by Western blot to detect the levels of phospho-IκBα and phospho-p65 80 , 81 .…”

“…RAW264.7 macrophages (2 × 10 6 ) were seeded in 60 mm cell culture plates. After overnight incubation cells were initially treated with IKKβ inhibitor (25 μM, SC-514, Sigma) 68 for 1 h to inhibit NF-kB signaling pathway and then cells were treated with LPS (1 μg/mL) and incubated for additional period of time 4 h. Cells were harvested, total RNA was isolated using TRIzol reagent, reverse transcribed to cDNA and analyzed by qPCR for the expression of HOTAIR, IL-6 and iNOS. GAPDH was used as control.…”

Upregulation of KSRP by miR‐27b attenuates schistosomiasis‐induced hepatic fibrosis by targeting TGF‐β1

“…KH‐type splicing regulatory protein is known to be one of the most important mRNA destabilizing proteins . KSRP can regulate the expression of proteins with important immune functions, such as iNOS, COX‐2, IL‐8, and CX3CL1 . Our study demonstrated that upregulation of KSRP destabilized TGF‐β1 mRNA through interacting with the ARE within its 3′UTR in hepatocytes and non‐parenchymal cells.…”

“…Although transcription is an essential first step in the regulation of inflammatory cytokine/chemokine expression, posttranscriptional regulation, including mRNA decay, is key to control protein synthesis . The 3′‐untranslated region (3′UTR) of mRNA represents an important element in the posttranscriptional regulation of inflammatory cytokines/chemokines . The KH‐type splicing regulatory protein (KSRP, also known as KHSRP) is an RNA‐binding protein that recognizes the AU‐rich elements (AREs) within the 3′UTRs of mRNAs and controls their stabilities in the cytoplasm .…”

E3 Ligase FBXW2 Is a New Therapeutic Target in Obesity and Atherosclerosis

“…KSRP, an RNA binding protein that destabilizes mRNAs via adenylate/uridylate-rich elements (AREs), has been reported to negatively modulate a subset of cytokines and chemokines by regulating mRNA stability and translational efficiency. [19,20] To further verify the interaction between FBXW2 and KSRP, protein extracts from Raw264.7 cells cotransfected with Myc-FBXW2 and Flag-KSRP were subjected to co-IP assay, which demonstrated that FBXW2 coprecipitated with KSRP ( Figure 4D). Moreover, we investigated the functional domains mediating the association of FBXW2 and KSRP.…”