Cloning and characterization of a LPS-regulatory gene having an LPS binding domain in kuruma prawn Marsupenaeus japonicus

Molecular cloning, genomic organization and functional analysis of an anti-lipopolysaccharide factor from Chinese mitten crab Eriocheir sinensis

“…The identification and characterization of immune effectors are believed to be helpful for elucidation of immune defence mechanisms and for the diseases control in crab aquaculture because of their potential use as therapeutic agents and genetic improvement biomarkers on disease-resistant strain selection. In crabs, many AMPs has been identified and characterized up to now, such as 6.5 kDa proline-rich cationic protein [33], Callinectin [34], Carcinin [35], Scygonadin [36] and ALF [9,[14][15][16][17][18][19][20]. However, molecular features and functional studies on AMP genes were still deficient in Chinese mitten crab.…”

“…The untreated crabs and crabs that received an injection of 50 ml PBS were used as the blank group and the control group, respectively. The injected crabs were returned to water tanks and three individuals were randomly collected at 2,4,6,8,12,16,24,32,48 and 72 h post-injection. The haemolymphs from the blank, control and challenge groups were collected using a syringe from cheliped in an equal volume of anticoagulant modified Alsever solution (27 mM sodium citrate, 336 mM NaCl, 115 mM glucose, 9 mM EDTA, pH 7.0) [27], and centrifuged at 1000g, 4 1C for 10 min to harvest the haemocytes.…”

“…Because one of the seriously infectious bacterial pathogens in Chinese mitten crab is Gram-negative bacteria in the genus of Vibrio [9], in which lipopolysaccharide (LPS) is believed to play an important role in the process of pathophysiology, identifying and characterizing AMPs with LPS binding or neutralizing activity is particularly attractive to control E. sinensis disease. In the last decades, several LPS-binding proteins or peptides had been characterized in vertebrates and invertebrates, such as bactericidal increasing protein (BPI) [10], lipopolysaccharides-binding protein (LBP) [10], lipopolysaccharide and b-1,3-glucan-binding protein (LGBP) [11,12], C-reactive protein [13] and anti-lipopolysaccharide factor (ALF) [9,[14][15][16][17][18][19][20].…”

“…Subsequent studies indicated that ALF from L. polyphemus exhibited strong antibacterial activity against Gram-negative R-type bacteria through neutralizing the lipid A, a common toxic moiety of LPS [21,22], and also the inhibitory effect on the growth of Gram-positive bacteria. Afterward, similar proteins were identified from the haemocytes of Litopenaeus vannamei [15], T. tridentatus [20], Penaeus monodon [17,18], Fenneropenaeus chinensis [9], Marsupenaeus japonicus [16], Pacifastacus leniusculus [23], and Scylla paramamosain [24], etc. The expression profile of ALFs indicated that the mRNA transcripts for the protein could be induced by Vibrio infection [9,18] or LPS administration [16], suggesting their crucial roles in crustacean innate immunity.…”

“…Afterward, similar proteins were identified from the haemocytes of Litopenaeus vannamei [15], T. tridentatus [20], Penaeus monodon [17,18], Fenneropenaeus chinensis [9], Marsupenaeus japonicus [16], Pacifastacus leniusculus [23], and Scylla paramamosain [24], etc. The expression profile of ALFs indicated that the mRNA transcripts for the protein could be induced by Vibrio infection [9,18] or LPS administration [16], suggesting their crucial roles in crustacean innate immunity. More importantly, the discovery of various ALFs and their derivatives had attracted great interest in mammalian health as candidate therapeutic or prophylactic agents for the management of septic shocks [22,25,26].…”