CRISPR/Cas9-Mediated Knockout of tnfaip1 in Zebrafish Plays a Role in Early Development

TNF α-induced protein 1 (TNFAIP1) was first identified in human umbilical vein endothelial cells and can be induced by tumor necrosis factor α (TNFα). Early studies have found that TNFAIP1 is involved in the development of many tumors and is closely associated with the neurological disorder Alzheimer's disease. However, little is known about the expression pattern of TNFAIP1 under physiological conditions and its function during embryonic development. In this study, we used zebrafish as a model to illustrate the early developmental expression pattern of tnfaip1 and its role in early development. First, we examined the expression pattern of tnfaip1 during early zebrafish development using quantitative real-time PCR and whole mount in situ hybridization and found that tnfaip1 was highly expressed in early embryonic development and, subsequently, expression became localized to anterior embryonic structures. To investigate the function of tnfaip1 during early development, we constructed a model of a stably inherited tnfaip1 mutant using the CRISPR/Cas9 system. Tnfaip1 mutant embryos showed significant developmental delays as well as microcephaly and microphthalmia. At the same time, we found decreased expression of the neuronal marker genes tuba1b, neurod1, and ccnd1 in tnfaip1 mutants. Analysis of transcriptome sequencing data revealed altered expression of the embryonic development related genes dhx40, hspa13, tnfrsf19, nppa, lrp2b, hspb9, clul1, zbtb47a, cryba1a, and adgrg4a in the tnfaip1 mutants. These findings suggest an important role for tnfaip1 in the early development of zebrafish.