Genomic organization and promoter characterization of FcCTL, a C-type lectin-like protein in Fenneropenaeus chinensis

Diseases caused by viruses are the greatest challenge to worldwide shrimp aquaculture. C-type lectins may play an important role in shrimp immunity. The gene encoding FcCTL, a C-type lectin-like protein, was isolated from Fenneropenaeus chinensis and characterized. This gene was composed of five exons spanning 2470 base pairs (bp). Intron 1 contained a possible promoter and many potential transcription factor binding sites, such as those for TATA binding protein, CREB, SRF, Ttk and three sites for HSFs. The 5′-flanking sequences (723 bp) of FcCTL contained typical CTF (CAAT box) and transcriptional regulatory elements, such as CF1, CF2-II and HSEs, observed in immunity-related genes in other arthropods. A series of FcCTL promoter sequences, especially the full-length promoter, generated an increase in luciferase expression relative to the promoter-less vector; furthermore, the expression of FcCTL was induced by heat shock and white spot syndrome virus (WSSV) challenge. These results extended our previous findings and provided insights into the molecular regulation of FcCTL gene expression, which would be helpful for shrimp viral disease control.

► We have cloned the gene and promoter of a C-type lectin-like protein. ► We have analyzed the sequences. ► We have analyzed the activity of the promoter in vitro.