Tollip‐deficient zebrafish display no abnormalities in development, organ morphology or gene expression in response to lipopolysaccharide

Abstract

Tollip is a multifunctional adaptor protein implicated in innate immunity, lysosomal trafficking/autophagy of protein aggregates and various signaling processes in mammalian models. To verify evolutionary conservation of these functions, we used CRISPR/Cas9 editing to construct a zebrafish line bearing a stable tollip knockout. In contrast to previously reported tollip morphants, Tollip-deficient fish display normal development until adulthood, are fertile, and have no apparent physiological defects. When challenged with lipopolysaccharide (LPS), inflammatory gene expression is unaffected. Moreover, Tollip deficiency does not aggravate swimming deficiency resulting from lysosomal dysfunction and proteotoxicity in a fish model of Gaucher disease. Thus, individual functions of Tollip may be organism-specific or manifest only upon certain conditions/challenges or disease backgrounds.

Optimising commercial traits through gene editing in aquaculture: Strategies for accelerating genetic improvement

“…Studies focusing on innate immunity have targeted immune-related genes that regulate gene expression or disturb certain pathways. [338][339][340] Pattern recognition receptors (PRRs) detect the presence of pathogen-associated molecular patterns. 341,342 In fishes, retinoic acid-inducible gene receptors (RIGR) and toll-like receptors (TLRs) are two key classes of PRRs that play a major role in innate immunity.…”

“…345,[348][349][350][351] Several recent studies have focused on knocking out genes related to TLRs to better characterise their role in innate immunity; these studies included rohu carp (Labeo rohita), zebrafish (Danio rerio) and olive flounder (Paralichthys olivaceus). 338,339,352 Additional studies have targeted genes in fishes that are known to affect immunity in mammal models allowing for a better understanding of the immune pathways present in fishes. 353,354 For example, Ouyang et al…”

“…Therefore, gene editing research for disease‐resistant traits has primarily focused on innate immunity or gene function after exposure. Studies focusing on innate immunity have targeted immune‐related genes that regulate gene expression or disturb certain pathways 338–340 . Pattern recognition receptors (PRRs) detect the presence of pathogen‐associated molecular patterns 341,342 .…”

“…TLRs and RIGR are membrane glycoproteins that activate interferons or nuclear factor pathways once they recognise pathogen‐associated molecular patterns on the surface of a cell 345,348–351 . Several recent studies have focused on knocking out genes related to TLRs to better characterise their role in innate immunity; these studies included rohu carp ( Labeo rohita ), zebrafish ( Danio rerio ) and olive flounder ( Paralichthys olivaceus ) 338,339,352 . Additional studies have targeted genes in fishes that are known to affect immunity in mammal models allowing for a better understanding of the immune pathways present in fishes 353,354 .…”