TitleThe Ahr2-Dependent wfikkn1 Gene Influences Zebrafish Transcriptome, Proteome, and Behavior.
Publication TypeJournal Article
Year of Publication2022
AuthorsShankar, P, Garcia, GR, La Du, JK, Sullivan, CM, Dunham, CL, Goodale, BC, Waters, KM, Stanisheuski, S, Maier, CS, Thunga, P, Reif, DM, Tanguay, RL
JournalToxicol Sci
Date Published2022 05 26
KeywordsAnimals, Embryo, Nonmammalian, Polychlorinated Dibenzodioxins, Polycyclic Aromatic Hydrocarbons, Proteome, Receptors, Aryl Hydrocarbon, Transcriptome, Zebrafish, Zebrafish Proteins

The aryl hydrocarbon receptor (AHR) is required for vertebrate development and is also activated by exogenous chemicals, including polycyclic aromatic hydrocarbons (PAHs) and 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). AHR activation is well-understood, but roles of downstream molecular signaling events are largely unknown. From previous transcriptomics in 48 h postfertilization (hpf) zebrafish exposed to several PAHs and TCDD, we found wfikkn1 was highly coexpressed with cyp1a (marker for AHR activation). Thus, we hypothesized wfikkn1's role in AHR signaling, and showed that wfikkn1 expression was Ahr2 (zebrafish ortholog of human AHR)-dependent in developing zebrafish exposed to TCDD. To functionally characterize wfikkn1, we made a CRISPR-Cas9 mutant line with a 16-bp deletion in wfikkn1's exon, and exposed wildtype and mutants to dimethyl sulfoxide or TCDD. 48-hpf mRNA sequencing revealed over 700 genes that were differentially expressed (p  1) between each pair of treatment combinations, suggesting an important role for wfikkn1 in altering both the 48-hpf transcriptome and TCDD-induced expression changes. Mass spectrometry-based proteomics of 48-hpf wildtype and mutants revealed 325 significant differentially expressed proteins. Functional enrichment demonstrated wfikkn1 was involved in skeletal muscle development and played a role in neurological pathways after TCDD exposure. Mutant zebrafish appeared morphologically normal but had significant behavior deficiencies at all life stages, and absence of Wfikkn1 did not significantly alter TCDD-induced behavior effects at all life stages. In conclusion, wfikkn1 did not appear to be significantly involved in TCDD's overt toxicity but is likely a necessary functional member of the AHR signaling cascade.

Alternate JournalToxicol Sci
PubMed ID35377459
PubMed Central IDPMC9308396
Grant ListS10OD020111 / NH / NIH HHS / United States
R01 ES030017 / ES / NIEHS NIH HHS / United States
T32 ES007060 / ES / NIEHS NIH HHS / United States
S10 OD020111 / OD / NIH HHS / United States
P42 ES016465 / ES / NIEHS NIH HHS / United States