Null involvement of microRNAs (miRNAs) in the anxiety and obesity link in zebrafish larvae. (A,B) PCA graphs of anxiety and obesity, respectively. (C) Volcano plot of anxiety model. Red points: DE in the anxiety model, FDR < 0.05, and absolute log2 fold change > 0.58 (>1.5 and <0.67 fold change). The “dre-miR” prefix has been removed from miRNA labels to enable better visualization. (D) Volcano plot of obesity model. Gold points: DE in the obesity model, FDR < 0.05, and absolute log2 fold change > 0.58 (>1.5 and <0.67 fold change). (E) Experimental design: zebrafish larvae (6 days post-fertilization (dpf)) were fed either the standard diet (SD) or high-fat diet (HFD). At age 15 dpf, a group of the standard diet-fed larvae were further divided into caffeine-exposed larvae (CAF) and the controls (NO). Following caffeine exposure (0.5 h) of the CAF larvae, larvae of all treatments were snap-frozen until RNA extraction for RNA-seq. (F) qRT-PCR of dre-miR-738 in the anxiety and obesity models, Student’s t-test, n = 3–8 (10–30 larvae/replicate, and 1–3 independent experiments, where RNA of one of the experiments had been used in RNA-seq. The reference was the average of three miRNAs: dre-miR-let7a, dre-miR-125b-5p, and dre-miR-26a-5p. **—p < 0.01.