Cloning and characterization of the LvCTL genes encoding C-type lectin from white-leg shrimp ( Litopenaeus vannamei).

Background: Lectins are carbohydrate-binding protein domains. The C-type lectin designates a requirement for calcium for binding. Proteins contain C-type lectin domains that have a diverse range of functions, including cell-cell adhesion, immune response to pathogens, and apoptosis. This study aimed to investigate the characters of LvCTL-encoding genes from white-leg shrimp ( Litopenaeus vannamei) in Central Vietnam. Methods: Two PCR products (LvCTL3 and LvCTL4) were cloned and sequenced. The structure and characterization of LvCTL proteins were predicted using bioinformatics tools. Results: The results showed that the LvCTL3 gene was 444 nucleotides in length and 98.87% similar to the published LvCTL3 gene (accession number: KF156943). The polypeptide sequence had 147 amino acids, which were 97.28% identical to the reference sequence (AGV68681) and the LvCTL4 gene had a length of 417 nucleotides and homology of 99.52% compared to the published gene (KM387560). The deduced polypeptide sequence had 138 amino acids, and was 100% similar to the reference sequence (AKA64754). The LvCTL3 had a molecular weight of 16.91 kDa and an isoelectric point (pI) of 4.66, while LvCTL4 had 15.75 and 4.58 kDa, respectively. The structure prediction results showed that LvCTL3 and LvCTL4 had one domain (CTLD), LvCTL3 had two α helices and nine ß sheets, and LvCTL4 had two α helices and eight ß sheets. Conclusions: Our results provide essential information for the heterologous expression and biosynthesis production of C-type lectins.

Characterization of ddx4 and dnd Homologs in Snakeskin Gourami (Trichopodus pectoralis) and Their Expression Levels during Larval Development and in Gonads of Males and Females.

The purpose of this study was to clone and characterize ddx4 and dnd1 homologs in snakeskin gourami (Trichopodus pectoralis) and to determine their expression levels during larval development and in the gonads of males and females. Both cDNAs contained predicted regions that shared consensus motifs with the ddx4 family in teleosts and the dnd family in vertebrates. Phylogenetic tree construction analysis confirmed that these two genes were clustered in the families of teleosts. Both ddx4 and dnd1 mRNAs were detectable only in the gonads, particularly in germ cells. These two genes were expressed during early larval development. The expression of ddx4 was high during early larval development and decreased with increasing developmental age, whereas dnd1 expression increased with developmental age. In adult fish, the expression levels of both genes were higher in the ovary than in the testis. Overall, these findings provide valuable molecular information on ddx4 and dnd, and can be applied in future reproductive biological studies relating to sex dimorphism in snakeskin gourami.