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bioRxiv · 10.1101/2022.04.27.489691

Targeting Apollo-NADP+ to image NADPH generation in pancreatic beta-cell organelles

Chang, H. H.·Bennett, A. M.·Cameron, W. D.·Floro, E.·Au, A.·McFaul, C. M.·Yip, C. M.·Rocheleau, J. V.
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Abstract

NADPH/NADP+ redox state supports numerous reactions related to cell growth and survival; yet the full impact is difficult to appreciate due to organelle compartmentalization of NADPH and NADP+. To study glucose-stimulated NADPH production in pancreatic beta-cell organelles, we targeted the Apollo-NADP+ sensor by first selecting the most pH stable version of the single colour sensor. We subsequently targeted mTurquoise2-Apollo-NADP+ to various organelles and confirmed activity in the cytoplasm, mitochondrial matrix, nucleus, and peroxisome. Finally, we measured the glucose- and glutamine-stimulated NADPH responses by single and dual colour imaging of the targeted sensors. Overall, we developed multiple organelle-targeted Apollo-NADP+ sensors to reveal the prominent role of beta-cell mitochondria in determining NADPH production in the cytoplasm, nucleus, and peroxisome.

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Chang, H. H., Bennett, A. M., Cameron, W. D., Floro, E., Au, A., McFaul, C. M., Yip, C. M., Rocheleau, J. V.. 2022-04-28. Targeting Apollo-NADP+ to image NADPH generation in pancreatic beta-cell organelles. https://doi.org/10.1101/2022.04.27.489691

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