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Targeting Apollo-NADP⁺ to Image NADPH Generation in Pancreatic Beta-Cell Organelles.

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-color 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-color 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.

SUBMITTER: Chang HH

PROVIDER: S-EPMC9706804 | biostudies-literature | 2022 Nov

REPOSITORIES: biostudies-literature

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Targeting Apollo-NADP+ to Image NADPH Generation in Pancreatic Beta-Cell Organelles.

Chang Huntley H HH Bennett Alex M AM Cameron William D WD Floro Eric E Au Aaron A McFaul Christopher M CM Yip Christopher M CM Rocheleau Jonathan V JV

ACS sensors 20221021 11

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-color sensor. We subsequently targeted mTurquoise2-Apollo-NADP+ to various organelles ...[more]

PMID: 36269889

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