TEPs (thioester containing proteins) and ficolins: structure and function in a crustacean
2012 (English)Conference paper, Poster (Other academic)
Place, publisher, year, edition, pages
IdentifiersURN: urn:nbn:se:uu:diva-189811OAI: oai:DiVA.org:uu-189811DiVA: diva2:582336
The 12th Congress of the International Society of Developmental and Comparative Immunology,Hilton Fukuoka Sea Hawk Hotel, Fukuoka city, Japan, 9th to 13th July, 2012.
This is the first report of an insect TEP-like protein in a crustacean. Pl-TEPs have the basic domain structure and functionally important residues ,and their mRNA was detected in different parts of the body, suggesting that they may have different functions. Pl-A2M1 was mainly expressed in hemocytes and Pl-A2M2 was highly expressed in heart and nerve, while Pl-TEP was exclusively expressed in cuticular tissues such as gill and intestine. RNA interference of Pl-TEP in vivo resulted in that these animals were slightly less resistant when fed with the bacterium, Pseudomonas libanensis/gessardii. Furthermore, when TEP activity was blocked using methylamine followed by bacterial feeding, the animals were killed to a higher extent compared to a control group. Taken together, this indicates that Pl-TEP and/or Pl-A2M1, Pl-A2M2 may be important for the immune defense in crayfish intestine and function as a pattern recognition protein in cray␣sh cuticular tissues.
To isolate pathogen-associated molecular patterns (PAMPs)-binding molecules, the bacter- ium, Staphylococcus aureus was used as an affinity matrix to find bacteria-binding proteins in the plasma of the freshwater crayfish, Pacifastacus leniusculus. Two new bacteria-binding ficolin-like proteins (FLPs) were identified by 2-DE and MS analysis. The FLPs have a fibri- nogen-related domain (FReD) in their C-terminal and a repeat region in their N-terminal regions with putative structural similarities to the collagen-like domain of vertebrate ficolins and mannose binding lectins (MBLs).. Recombinant FLPs exhibited agglutination activity of Gram-negative bacteria Escherichia coli and Aeromonas hydrophila in the presence of Ca21. The FLPs could bind to A. hydrophila, E. coli as well as S. aureus as judged by bacteria adsorption. Moreover, the FLPs may help crayfish to clear Gram-negative bacteria, but not Gram-positive bacteria which had been injected into the hemolymph.2013-01-042013-01-042013-01-08Bibliographically approved