Cloning and Characterisation of Multiple Ferritin Isoforms in the Atlantic Salmon (Salmo salar)

Abstract

Ferritin is a highly-conserved iron-storage protein that has also been identified as an acute phase protein within the innate immune system. The iron-storage function is mediated through complementary roles played by heavy (H)-chain subunit as well as the light (L) in mammals or middle (M)-chain in teleosts, respectively. In this study, we report the identification of five ferritin subunits (H1, H2, M1, M2, M3) in the Atlantic salmon that were supported by the presence of iron-regulatory regions, gene structure, conserved domains and phylogenetic analysis. Tissue distribution analysis across eight different tissues showed that each of these isoforms is differentially expressed. We also examined the expression of the ferritin isoforms in the liver and kidney of juvenile Atlantic salmon that was challenged with Aeromonas salmonicida as well as in muscle cell culture stimulated with interleukin-1β. We found that each isoform displayed unique expression profiles, and in certain conditions the expressions between the isoforms were completely diametrical to each other. Our study is the first report of multiple ferritin isoforms from both the H- and M-chains in a vertebrate species, as well as ferritin isoforms that showed decreased expression in response to infection. Taken together, the results of our study suggest the possibility of functional differences between the H- and M-chain isoforms in terms of tissue localisation, transcriptional response to bacterial exposure and stimulation by specific immune factors.

Global gene expression patterns of grass carp following compensatory growth

“…GDF-15 is associated with appetite, and high expression level of GDF-15 may reduce appetite and weight in mice [ 73 ]. Ferritin (middle subunit) is a protein involved in response to cellular emergencies [ 74 ]. Down-regulation of these genes suggests that following re-feeding, fish exit from the emergency response, and the presence of food stimulates appetite.…”

Transcriptome profiling reveals that feeding wild zooplankton to larval Atlantic cod (Gadus morhua) influences suites of genes involved in oxidation-reduction, mitosis, and selenium homeostasis

“…up-regulated in the APR: e.g. ferritin, ceruloplasmin, and hepcidin [ 54 , 55 ]) and CCAAT/enhancer-binding protein delta (associated with GO term “acute-phase response”) were identified by microarray in the current study as being significantly up-regulated in both RA and RA-PH larvae compared with RA-Zoo larvae at the 9 mm stage (Additional file 2 : Table S2). Therefore, the suppressed selenoprotein Pa transcript expression observed in 9 mm RA and RA-PH larvae may be due to an APR that was potentially related to nutritional insufficiency.…”

Ferritin M of Paralichthys olivaceus possesses antimicrobial and antioxidative properties

“…Ferritin synthesis is known to be regulated by pathogen infection (Andersen et al 1995(Andersen et al , 1998Mignogna et al 2002;Zhang et al 2010;Zheng et al 2010;Harikrishnan et al 2011;Wang et al 2011;Elvitigala et al 2013;Lee et al 2014). For example, upon exposure to bacterial pathogens, the expressions of the M ferritins of rock bream, tongue sole, turbot, and large yellow croaker are enhanced (Zhang et al 2010;Zheng et al 2010;Wang et al 2011;Elvitigala et al 2013), whereas the expression of the M ferritin of Atlantic salmon is inhibited .…”

“…In fish, M ferritin has been identified in a number of species including Oplegnathus fasciatus, Chionodraco rastrospinosus, Epinephelus bruneus, Cynoglossus semilaevis, Scophthalmus maximus, Pseudosciaena crocea, Trematomus bernacchii, and Salmo salar (Andersen et al 1995(Andersen et al , 1998Mignogna et al 2002;Giorgi et al 2008;Zhang et al 2010;Harikrishnan et al 2011;Wang et al 2011;Elvitigala et al 2013;Scudiero et al 2013;Lee et al 2014). However, only a few of these ferritins were shown to possess iron binding and/or antioxidative potential.…”