SZNF (Sus scrofa zinc finger CCHC domain containing 3) is a post-transcription regulation factor, belonging to CCHC zinc finger proteins. Cyadox is a novel quinoxaline drug with antibacterial and growth promotion effects. In this study, we investigated the pharmacological mechanism of cyadox mediated by SZNF. Firstly, signaling pathways related to cyadox-induced SZNF expression were studied. The results showed that the mRNA level of SZNF reached the peak as early as 4 h after 2 μM cyadox treatment in swine hepatocytes. Several signaling pathways, including JAK2/STAT1, PI3K/Akt, TGF-β/Smad3 and p38, might play critical roles in regulation of SZNF. The JAK2/STAT1, JAK2/PI3K/Akt, PI3K/Akt and myD88 & TAK1 & ASK1 /P38 signaling pathways were firstly activated after cyadox treatment in swine hepatocyte, the TGF-β/Smad3 signaling pathway was activated later. Then given the characteristic of RNA binding of CCHC zinc finger proteins, the target mRNAs binding with SZNF were detected by RNA immunoprecipitation coupled to sequencing (RIP-seq) in PK-15 cells treated with cyadox. The RIP-Seq results showed that the bound mRNAs of 45 genes and 93 genes by SZNF protein were increased and decreased, respectively in cyadox-treated PK-15 cells compared with blank sample. With bioinformatics analysis, we showed that cyadox might exert its antibacterial and growth promotion effect by regulating SZNF-associated target genes in post-transcriptional level, such as genes related to growth (MLXIP, CKS2) and inflammation (LGALS3, PLAU). Thus, our results indicated that SZNF can post-transcriptionally regulate its target genes related to growth and inflammatory in cyadox-treated cells, which may explain the pharmacological mechanism of this drug.
Keywords: Cyadox; PK-15 cells; RIP-Seq; SZNF; Signaling pathway; Swine hepatocytes.
Copyright © 2018. Published by Elsevier Masson SAS.