Fig. 2.

Fig. 2. In vivo imaging of mVenus-tagged Apollo-NADP⁺ expressed in pancreatic β cells of 5-dpf zebrafish embryos.

(A) Top: Tol2 transposon construct used to express Apollo-NADP⁺ in zebrafish. Expression is targeted to β cells using a zebrafish insulin promoter. Bottom: Apollo-NADP⁺ switches between a monomer and homodimeric state in response to changes in NADP⁺ concentration. (B) In vivo pancreatic islet slice images from 5-dpf Apollo-NADP⁺ transgenic zebrafish embryos, taken at 3-, 15-, and 30-μm depths. (C) In vivo fluorescence anisotropy imaging of 5-dpf islets of Apollo-NADP⁺ zebrafish embryos, taken at 1-μm intervals. n = 26 embryos. (D) In vivo time series fluorescence anisotropy imaging of 5-dpf islets of Apollo-NADP⁺ transgenic zebrafish in response to treatment with glucose (Glu) or diamide (Dia), taken at 5-min intervals. n = 8 to 15 embryos; **P < 0.01 and ****P < 0.0001. (E) In vivo time series fluorescence anisotropy imaging of a single islet slice from 5-dpf Apollo-NADP⁺ transgenic zebrafish embryos, taken at 10-s intervals. Diamide (10 mM) was added at 5 min and removed at 10 min. n = 15 embryos.