Molecular cloning and expression analysis of sea bass (Dicentrarchus labrax L.) tumor necrosis factor-alpha (TNF-alpha).
In the search for pro-inflammatory genes in sea bass a TNF-alpha gene was cloned and sequenced. The sea bass TNF-alpha (sbTNF-alpha) putative protein conserves the TNF-alpha family signature, as well as the two cysteines usually involved in the formation of a disulfide bond. The mouse TNF-alpha Thr-Leu cleavage sequence and a potential transmembrane domain were also found, suggesting that sbTNF-alpha exists as two forms: a approximately 28 kDa membrane-bound form and a approximately 18.4 kDa soluble protein. The single copy sbTNF-alpha gene contains a four exon-three intron structure similar to other known TNF-alpha genes. Homology modeling of sbTNF-alpha is compatible with the trimeric quaternary architecture of its mammalian counterparts. SbTNF-alpha is constitutively expressed in several unstimulated tissues, and was not up-regulated in the spleen and head-kidney, in response to UV-killed Photobacterium damselae subsp. piscicida. However, an increase of sbTNF-alpha expression was detected in the head-kidney during an experimental infection using the same pathogen.
Nascimento
Diana S
DS
IBMC - Instituto de Biologia Molecular e Celular, Universidade do Porto, Rua do Campo Alegre 823, 4150-180 Porto, Portugal. dsn@ibmc.up.pt
Pereira
Pedro J B
PJ
Reis
Marta I R
MI
do Vale
Ana
A
Zou
Jun
J
Silva
Manuel T
MT
Secombes
Christopher J
CJ
dos Santos
Nuno M S
NM
D000818:Animals; D001492:Bass / Q000235:genetics* / Q000378:metabolism* / Q000382:microbiology; D003001:Cloning, Molecular; D005393:Fish Diseases / Q000378:metabolism / Q000382:microbiology; D020869:Gene Expression Profiling / Q000662:veterinary; D005786:Gene Expression Regulation; D016905:Gram-Negative Bacterial Infections / Q000378:metabolism / Q000662:veterinary; D053583:Interleukin-1beta / Q000235:genetics; D008958:Models, Molecular; D008969:Molecular Sequence Data; D010776:Photobacterium / Q000502:physiology; D010802:Phylogeny; D017434:Protein Structure, Tertiary; D020133:Reverse Transcriptase Polymerase Chain Reaction; D016415:Sequence Alignment; D014409:Tumor Necrosis Factor-alpha / Q000737:chemistry / Q000235:genetics*
D053583:Interleukin-1beta; D014409:Tumor Necrosis Factor-alpha