Functional convergence of invertebrate and vertebrate cytokine-like molecules based on a similar lectin-like activity.
It is generally accepted that the action of cytokines results from their binding to specific receptors. However, many cytokines possess lectin-like activity that may be essential for the expression of their full biological activities. This review focuses on the physiological relevance of the lectin-like activity of cytokines during the innate immune response in mammals, using TNF as an illustrative example. Moreover, we will show that TNF displays functional analogies with a defense molecule from the earthworm Eisenia foetida termed CCF. These analogies are not reflected by primary sequence homology between CCF and TNF but are particularly based on a similar lectin-like activity/domain. Hence, from a phylogenetic point of view, the lectin-like activity/domain of CCF and TNF may represent an essential recognition mechanism that has been functionally conserved during the innate immune response of invertebrates and vertebrates as a result of convergent evolution.
Department of Immunology, Parasitology and Ultrastructure, Flemish Interuniversity Institute for Biotechnology, Free University Brussels (VUB), Pleinlaan 2, 1050 Brussels, Belgium.
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A
Beschin
M
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Bilej
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S
Magez
R
R
Lucas
P
P
De Baetselier
D000818:Animals; D016207:Cytokines / Q000502:physiology*; D003603:Cytotoxins / Q000502:physiology; D006790:Host-Parasite Interactions / Q000276:immunology; D007113:Immunity, Innate; D007448:Invertebrates / Q000276:immunology*; D037102:Lectins / Q000502:physiology*; D009835:Oligochaeta / Q000276:immunology; D014409:Tumor Necrosis Factor-alpha / Q000502:physiology; D014714:Vertebrates / Q000276:immunology*
D016207:Cytokines; D003603:Cytotoxins; D037102:Lectins; D014409:Tumor Necrosis Factor-alpha; C094795:coelomic cytolytic factor 1, Eisenia fetida