Fig. 2

Fasting induces the rapid exacerbation of pex5^−/− leading to early mortality. a RFP-SKL was detected using the Xla.Eef1a1:RFP-SKL transgenic zebrafish at 2 dpf in the muscle cells and at 5 dpf in the liver sections of WT and pex5^−/−. Note that the SKL signal is diffusely detected in the liver cells of pex5^−/− at 5 dpf. Scale bar = 5 μm. b Endogenous Abcd3 proteins were shown by performing immunofluorescence at 2 dpf in the muscle cells and at 5 dpf in the liver sections of WT and pex5^−/−. Scale bar = 5 μm. Graphs show quantified signal intensity of Abcd3 at the indicated times and presented as the average with error bars indicating standard deviation. Statistical significance was determined using the Student’s t test in Microsoft Excel. c Survival curve shows a differential survival response between the WT and pex5^−/− zebrafish under fasting conditions. Experiments were performed at least three times and the average percentage of surviving animals was used to draw the curve (n = 40/genotype). Representative pictures of the WT and pex5^−/− fasted from 5 to 8 dpf are shown in lateral views with anterior to the left. Arrows point to the edematous gut area and deflated swim bladder in fasted pex5^−/− at 8 dpf. Scale bar = 1 mm. d Representative pictures of WT and pex5^−/− fasted from 11 to 13 dpf are shown as indicated. Scale bar = 1 mm. e, f Peroxisome abundance was compared in the liver cells between the WT and pex5^−/− and between the feeding and fasting conditions using immunofluorescence for Abcd3. There was a marked disappearance of peroxisome abundance depending on the pex5 genotype and the nutritional status. Scale bar = 5 μm. Graphs show quantified signal intensity of Abcd3 under fed or fasted conditions at the indicated times and presented as the average with error bars indicating standard deviation. Statistical significance was determined using the Student’s t test in Microsoft Excel; ** indicates p values < 0.01