Genomic organisation of rainbow trout, Oncorhynchus mykiss TGF-β

Biochemical and functional characterisation of macrophage stimulating factors secreted by mitogen-induced goldfish kidney leucocytes

“…Hardie et al, (1998) isolated a rainbow trout TGF-gene and demonstrated the presence of TGFmessage by RT-PCR in trout blood leucocytes, kidney macrophages, brain, gill 182 and spleen but not liver. Recently, the genomic organisation of the rainbow trout TGF-was determined by generating contiguous clones by PCR (Daniels & Secombes, 1999). The high degree of conservation of piscine and mammalian TGF-and its known macrophage deactivating properties, suggests that TGF-may be a potential candidate for the macrophage deactivating activities observed in the present study.…”

Molecular characterisation of sea bream (Sparus aurata) transforming growth factor β1

“…Therefore, the introns that have been eliminated in the sea bream TGF 1 gene are equivalent to the trout TGF 1 introns 1 and 3. Sea bream TGF 1 has maintained an additional intron that divides in two what in higher vertebrates corresponds to exon 7, and that was only found up to now in the rainbow trout [28]. The presence of an intron in this position in these two species is striking, as analysis of the secondary structure of the protein reveals that this intron splits the region that codes for a beta sheet present in the mature peptide.…”

“…This was possible due to the fact that introns in lower vertebrates are much smaller in size [28,35]. Strikingly, only four introns were found whilst six introns have been found in all TGF genes of amphibians, birds, mammals and in the rainbow trout [28]. It is known that certain species su#er pressures to contract the genome size, that result in the loss of introns.…”

“…In the plaice, Pleuronectes platessa, three sequences, each one corresponding to a distinct isoform were identified [27]. The TGF gene was also sequenced and characterised in the rainbow trout [28]. Concerning other TGF family members, both the A and the B activin genes have been cloned from goldfish, Carassius aurata [29] and di#erent bone morphogenetic proteins [30] and growth/di#erentiation factors [31] belonging to the TGF superfamily were also isolated in the zebrafish, Danio rerio.…”

Immune Defences of Teleost Fish

“…The homologues so far described include IL-1β (Hong et al 2004 (Zou et al 2005), TNFα (Laing et al 2001) and type I antiviral interferons (Robertsen et al 2003). Adaptive regulatory cytokines and their signalling molecules already described include TGFβ, IL-2 and two IL-10 gene products (Daniels and Secombes 1999;Zou et al 2003;Bird et al 2005a;Diaz-Rosales et al 2009;Harun et al 2011) and SOCS-1-3 (Wang and Secombes 2008). By inference, IL-12, IL-18, IL-2, TNFα and IFNγ are all involved in the development and effector functions of Th 1 cells that drive CMI responses (Tc activation and delayed type hypersensitivity (DTH)) to intracellular-resident pathogens such as the bacterium Mycobacterium marinum and infectious pancreatic necrosis virus (IPNV).…”