Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
2429139 | Developmental & Comparative Immunology | 2014 | 9 Pages |
•An ECSIT gene (MjEcsit1) was cloned from shrimp Marsupenaeus japonicus.•MjEcsit 1 is transcribed in various tissues and induced by bacterial challenge.•RNAi of MjEcsit 1 increases the mortality of bacteria-challenged shrimp.•Knockdown of MjEcsit 1 decreases the bacterial clearance ability in vivo.•MjEcsit 1 has an important role in the antibacterial immunity of shrimp.
The Toll/Toll-like receptor (TLR) signaling pathway has an important role in the innate immunity of animals. Evolutionarily conserved signaling intermediate in Toll pathways (ECSIT) is a protein that functions as an adaptor protein for the Toll/TLR and bone morphogenetic protein signaling pathways. ECSIT is also a key component in the macrophage bactericidal activity of mammals. However, the function of ECSIT in crustaceans remains unclear. In this study, we cloned and identified a functional ECSIT homologue, MjECSIT 1, from kuruma shrimp Marsupenaeus japonicus. The complementary DNA of MjEcsit 1 is 1442 base pairs long, with an open reading frame of 1221 base pairs that encodes a 407-residue polypeptide. Transcripts of MjEcsit 1 are detected in hemocytes, gills, hepatopancreas, stomach, heart, intestines, testes, and ovaries. Such transcripts are upregulated by Gram-positive bacteria (Staphylococcus aureus) and Gram-negative bacteria (Vibrio anguillarum) injections. The knockdown of MjEcsit 1 by double-stranded RNA injection increases the sensitivity of M. japonicus to S. aureus challenge and weakens the bacterial clearance ability of M. japonicus in vivo. In addition, suppressing MjEcsit 1 restrains the upregulation of two anti-lipopolysaccharide factors by S. aureus injection. The results indicate that MjECSIT 1 is important in the antibacterial immunity of M. japonicus.