Fig. 6

Overexpression of core clock gene per2 or bhlhe41 increases cold tolerance. a The design of the Gal-UAS driven circadian clock gene expression construct is shown. H2AmCherry (red) is placed upstream of clock gene (green) that will be cleaved by a 2A peptide (yellow). b 1-Cell embryos were injected with indicated plasmids and examined under bright (upper row) and dark filed (bottom row through a rhodamine filter cube). Mosaic expression of mcherry indicates the expression of bmal, per2, or bhlhe41 in 48 hpf embryos. c Normalized expression level of clock genes compared to control embryos at 5 days post fertilization by qPCR (N = 3). d Scheme of cold recovery assay at 5 days post fertilization fish. e Classifications of swimming track recorded for 10 mins. f Quantitative analysis of swimming patterns for zebrafish larva transient expressed without (control) and with designated circadian clock gene at different time periods after recording. g Glucose concentration were measured in 4 dpf zebrafish larval lysate collected at different time point after cold shock. *P ≤ 0.05, **p ≤ 0.01