Critical roles of sea XXXX C-type lectin in non-self recognition and  bacterial clearance.

@entity462 @entity526 @entity794 @entity20874 @entity9688 @entity141 @entity2551 @entity3689 @entity7178
UNASSIGNED: C-type lectin is one important pattern recognition receptor (PRR) that plays crucial roles in multiple immune responses. A C-type lectin from sea @entity9688 @entity20874 (AjCTL-1) was characterized in the present study. The @entity3689 sequence of AjCTL-1 shared high similarities with other C-type lectins from invertebrates and vertebrates. The C-type lectin domain (CTLD) of AjCTL-1 contained a @entity141 -binding site 2 and four conserved @entity462 residues. AjCTL-1 mRNA expression patterns in tissues and after bacterial challenge were then analysed. Quantitative PCR revealed that AjCTL-1 mRNA was widely expressed in the tested tissues of healthy sea @entity9688 . The highest expression level occurred in gonad followed by body wall, coelomocytes, tentacle, intestinum and longitudinal muscle, and the lowest expression level was in respiratory tree. AjCTL-1 mRNA expression in coelomocytes was significantly induced by gram-negative @entity2551 and gram-positive @entity7178 , with different up-regulation patterns post-challenge. Recombinant AjCTL-1 exhibited the ability to bind peptidoglycan directly, agglutinate @entity7178 , @entity794 and @entity526 , in a @entity141 -dependant manner, and enhance the phagocytosis of coelomocytes against @entity526 in  vitro. The results indicated that AjCTL-1 could act as a PRR in @entity20874 and had critical roles in non-self recognition and bacterial clearance against invading microbes.
