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Abstract Mitochondria are well-characterized regarding their function in both energy production and regulation of cell death; however, the heterogeneity that exists within mitochondrial populations is poorly understood. Typically analyzed as pooled samples comprised of millions of individual mitochondria, there is little information regarding potentially different functionality across subpopulations of mitochondria. Herein we present a new methodology to analyze mitochondria as individual components of a complex and heterogeneous network, using a nanoscale and multi–parametric flow cytometry-based platform. We validate the platform using multiple downstream assays, including electron microscopy, ATP generation, quantitative mass-spectrometry proteomic profiling, and mtDNA analysis at the level of single organelles. These strategies allow robust analysis and isolation of mitochondrial subpopulations to more broadly elucidate the underlying complexities of mitochondria as these organelles function collectively within a cell.
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Regulating Mitochondrial pH with Light and Implications for Chemoresistance
Abstract Chemoresistance is one of the major challenges for cancer treatment, more recently ascribed to defective mitochondrial outer membrane permeabilization (MOMP), significantly diminishing chemotherapeutic agent‐induced apoptosis. A boron‐dipyrromethene (BODIPY) chromophore‐based triarylsulfonium photoacid generator (BD‐PAG) was used to target mitochondria with the aim to regulate mitochondrial pH and further depolarize the mitochondrial membrane. Cell viability assays demonstrated the relative biocompatibility of BD‐PAG in the dark while live cell imaging suggested high accumulation in mitochondria. Specific assays indicated that BD‐PAG is capable of regulating mitochondrial pH with significant effects on mitochondrial membrane depolarization. Therapeutic tests using chlorambucil in combination with BD‐PAG revealed a new strategy in chemoresistance suppression.
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- Award ID(s):
- 1726345
- PAR ID:
- 10237073
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Chemistry – A European Journal
- Volume:
- 27
- Issue:
- 1
- ISSN:
- 0947-6539
- Page Range / eLocation ID:
- p. 247-251
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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