A unique NLRC4 receptor from echinoderms mediates Vibrio phagocytosis via rearrangement of the cytoskeleton and polymerization of F-actin
Fig 2
The Ig domain of AjNLRC4 performs an immune recognition function.
(A) The bacterial binding activities of rAjNLRC4-EX and rAjNLRC4-IN were analyzed by using western blotting. Different bacteria were incubated with rAjNLRC4-EX and rAjNLRC4-IN, washed with PBS four times and then analyzed by western blotting with an anti-His antibody. TBS instead of rAjNLRC4-EX and rAjNLRC4-IN was used as the negative control. (B-E) The binding activities of rAjNLRC4-EX to different polysaccharides were analyzed with ELISA. Four polysaccharides were used for ELISA analysis (n = 5), including LPS from E. coli or V. splendidus, PGN and MAN. (F) rAjNLRC4-EX agglutinates different microbes in the presence of Ca2+. FITC-labeled microbes (green) were mixed with an equal volume of rAjNLRC4-EX (1 mg/ml) in the presence or absence of 10 mM CaCl2 and incubated at room temperature for approximately 1 h. BSA instead of rAjNLRC4-EX was used as the negative control. After incubation, agglutination reactions were observed under a fluorescence microscope.