Genomic organisation of the channel catfish Mx1 gene and characterisation of multiple channel catfish Mx gene promoters

Molecular structural and functional characterization of STAT1 gene regulatory region in teleost Channa argus

“…2). ISRE has been characterized in the promoter regions of teleost Mx and vig-2 genes from rainbow trout, pufferfish (Takifugu rubripes), zebrafish and channel catfish (Ictalurus puncatus) (Collet and Secombes, 2001;Boudinot et al, 2001;Yap et al, 2003;Altmann et al, 2004;Plant and Thune, 2008), and ISG15 from goldfish and Atlantic cod (Gadus morhua) (Liu et al, 2002;Seppola et al, 2007). The characteristic presence of ISRE and IRF-E are very interesting as they have shown ISGF3 and IRFs can bind to the promoter of IFNinduced genes.…”

“…However, luciferase assays indicated that two potential GAS elements have little effect on snakehead STAT1 promoter and intronic activity in response to hIFN-g in Hela cells. The promoter activity of IFN-induced genes has been demonstrated in rainbow trout, Chinook salmon (Oncorhynchus tshawytscha) and channel catfish Mx1 in vitro (Collet and Secombes, 2001;Collet et al, 2004;Plant and Thune, 2008). However, the regulation of cellular responses to IFN-g is very complex and is mediated by the equilibrium between the activities of the JAKs and STAT1 (Choi et al, 2007).…”

“…Viral and synthetic dsRNAs have been used to induce IFNs in different species in vitro and in vivo (Geiss et al, 2001;Saint-Jean and Pé rez-Prieto, 2006;Lu et al, 2008), subsequent IFNs were shown to up-regulate the expression of IFN-stimulated genes (ISGs), and also displayed the inducible expression of luciferase reporter genes coupled to their promoters (Collet and Secombes, 2001;Collet et al, 2004;Plant and Thune, 2008). Recently, the promoters for IFN-induced Mx1, gIP-10, LMP2 and TAP2 genes were shown to respond to IFN-a/b and IFN-g in rainbow trout (Oncorhynchus mykiss), although the promoter activity is quite variable between different IFN responsive genes that response to type I and type II IFNs (Jørgensen et al, 2007;Castro et al, 2008).…”

Expression regulation and functional characterization of a novel interferon inducible gene Gig2 and its promoter

“…This shows that the 5 flanking region cloned is a strong promoter, and negative regulatory structures might be lack in the promoter construct. Occurrence of basal expression due to leakiness of transcription is often seen in promoter-reporter assays, such as in fish type I IFN responsive promoters (Altmann et al, 2004;Plant and Thune, 2008) and IFN-␥ responsive promoters (Castro et al, 2008).…”

“…IFN-␥ molecules follow a similar pathway, but in this case, two STAT1 molecules dimerize to form a homodimer and bind to specific ␥-IFN activating sites (GAS) present in the promoters of IFN-␥ inducible genes (Platanias, 2005). Some fish ISGs have been verified to have typical ISRE motifs in their promoters, such as Mx (Altmann et al, 2004;Chen et al, 2006;Collet and Secombes, 2001;Ooi et al, 2006;Plant and Thune, 2008;Yap et al, 2003), IRFs (Collet et al, 2003;Collet and Secombes, 2002;Jia and Guo, 2008), major histocompatibility complex (MHC) class I genes (Dijkstra et al, 2003;Jorgensen et al, 2006), vig-2 (Boudinot et al, 2001), and ISG15 (Seppola et al, 2007), suggesting the existence of type I IFN inducible pathways in fish. Functional analysis showed that fish Mx promoters possess one or two ISRE motifs that appear necessary for its transcriptional regulation under exposure of Poly I:C (Ooi et al, 2006;Yap et al, 2003).…”