Molecular cloning and expression analysis of a F-type lectin gene from Japanese sea perch (Lateolabrax japonicus)

Abstract

The techniques of homology cloning and anchored PCR were used to clone the fucose-binding lectin (F-type lectin) gene from Japanese sea perch (Lateolabrax Japonicus). The full-length cDNA of sea perch F-lectin (JspFL) contained a 5' untranslated region (UTR) of 39 bp, an ORF of 933 bp encoding a polypeptide of 310 amino acids with an estimated molecular mass of 10.82 kDa and a 3' UTR of 332 bp. The searches for nucleotides and protein sequence similarities with BLAST analysis indicated that the deduced amino acid sequence of JspFL was homological to the Fucose-binding lectin in other fish species. In the JspFL deduced amino acid sequence, two tandem domains that exhibit the eel carbohydrate-recognition sequence motif were found. The temporal expressions of gene in the different tissues were measured by real-time PCR. And the mRNA expressions of the gene were constitutively expressed in tissues including spleen, head-kidney, liver, gill, and heart. The JspFL expression in spleen was different during the stimulated time point, 2 h later the expression level became up-regulated, and 6 h later the expression level became down-regulated. The result indicated that JspFL was constitutive and inducible expressed and could play a critical role in the host-pathogen interaction.

Diversified Carbohydrate-Binding Lectins from Marine Resources

“…Bianchet et al described that the fold structure of AAA, F-type lectin motifs, is widely distributed in other proteins even with lower sequence similarities, for example, C1 and C2 repeats of blood coagulation factor V, C-terminal domain of sialidase, N-terminal domain of galactose oxidase, APC10/DOC1 ubiquitin ligase and XRCC1 [121]. Furthermore, it has been reported that the several proteins are homologous to or contained with F-type lectin CRDs, of which examples include Streptococcus pneumoniae TIGR4 , furrowed receptor and CG9095 of Drosophila melanogaster , Xenopus laevis pentraxin 1 fusion protein, Microbulbifer degradans ZP_00065873.1, and yeast allantoises [121, 123] in addition to the tandem-repeated types of F-type lectins found in modern teleosts [64–66, 122], while F-type lectin CRD motifs are absent in genomes of higher vertebrates such as reptiles, birds, and mammals. …”

An Update of Lectins from Marine Organisms: Characterization, Extraction Methodology, and Potential Biofunctional Applications

“…Fucose-binding lectins (FTLs), also known as fucolectins, are characterized by a unique amino acid sequence motif, structural fold, and a nominal specificity for l -fucose, a feature of the eel carbohydrate-recognition sequence motif [ 70 ]. l -fucose is a non-reducing terminal sugar found in pro-and eukaryotic glycans, which may be released into the human intestinal lumen with the aid of hydrolytic activity of indigenous microbes and pathogens.…”

F-Type Lectins: A Highly Diversified Family of Fucose-Binding Proteins with a Unique Sequence Motif and Structural Fold, Involved in Self/Non-Self-Recognition

“…For MsaFBP32, an inflammatory challenge only increased the liver transcript levels in about three-fold over the relatively high basal expression levels ( 11 , 12 ), whereas for DlFBL protein levels were modestly enhanced by Vibrio alginolyticus infectious challenge ( 58 ). In the Japanese sea perch ( Lateolabrax japonicus ), the FTL JspFL was only upregulated in spleen, while it was also constitutively expressed in liver and gills ( 62 ). In contrast, LPS challenge significantly upregulated expression and increased secretion of FTLs in liver and gill tissue from A. japonica ( 15 ).…”