Identification and expression analysis of lipopolysaccharide-induced TNF-alpha factor gene in Chinese mitten crab Eriocheir sinensis.

Lipopolysaccharide-induced TNF-alpha factor (LITAF) is an important transcription factor in transcriptional regulation of TNF-alpha and other cytokines. Here we identified a full-length LITAF homolog cDNA, termed EsLITAF, that contains a 71 bp 5'-untranslated sequence, an open reading frame consisting of 381 bp, and a 208 bp 3'-untranslated sequence in Chinese mitten crab (Eriocheir sinensis), an economically important freshwater crustacean species in China. EsLITAF protein possesses a conserved C-terminal LITAF-like domain with two CXXC motifs and is comprised of 126 amino acids with a theoretical molecular mass of 13.1 kDa and an isoelectric point of 6.36. Blast search against GenBank database revealed that EsLITAF protein shared the highest sequence identity (84%) with the counterpart of Pacific white shrimp (Litopenaeus vannamei). EsLITAF mRNA transcript expresses ubiquitously in all examined tissues with the highest expression in hepatopancreas and lowest expression in haemocytes. Furthermore, EsLITAF mRNA expression could be significantly and rapidly induced in haemocytes by LPS and Poly(I:C) stimulations in vitro. Moreover, EsLITAF gene expression was up-regulated in haemocytes, gill and hepatopancreas after Edwardsiella tarda and Vibrio anguillarum challenges. Taken together, we have identified and characterized a new crustacean LITAF homolog from the Chinese mitten crab.