Structure of fish Toll-like receptors (TLR) and NOD-like receptors (NLR)
Autor
Ranjan Sahoo, Bikash
Institución
Resumen
Innate immunity driven by patter
n recognition receptor (PRR) protect
s the host from invading
pathogens. Aquatic animals like fish where the adaptive immunity is poorly developed majorly
rely on their innate immunity modulated by PRRs like toll
-like receptors (TLR) and NOD
-like
receptors (NLR). However, current development t
o improve the fish immunity via TLR/NLR
signaling is affected by a poor understanding of its mechanistic and structural features. This
review discusses the structure of fish TLRs/NLRs and its interaction with pathogen associated
molecular patterns (PAMPs) and downstream signaling molecules. Over the past one decade,
significant progress has been done in studying the structure of TLRs/NLRs in higher eukaryotes;
however, structural studies on fish innate immune receptors are undermined. Several novel TLR
genes are identified in fish that are absent in higher eukaryotes, but the function is still poorly
understood. Unlike the fundamental progress achieved in developing antagonist/agonist to
modulate human innate immunity, analogous studies in fish are nearly lacking due to structural
inadequacy. This underlies the importance of exploring the structural and mechanistic details of
fish TLRs/NLRs at an atomic and molecular level. This review outlined the mechanistic and
structural basis of fish TLR and NLR activation.