bims-smemid Biomed News
on Stress metabolism in mitochondrial dysfunction
Issue of 2023–12–03
two papers selected by
Deepti Mudartha, The International Institute of Molecular Mechanisms and Machines
  1. Protocol for evaluating mitochondrial morphology changes in response to CCCP-induced stress through open-source image processing software.
  2. Understanding differential aspects of microdiffusion (channeling) in the Coenzyme Q and Cytochrome c regions of the mitochondrial respiratory system.
  1. STAR Protoc. 2023 Nov 29. pii: S2666-1667(23)00712-8. [Epub ahead of print]4(4): 102745
    Protocol for evaluating mitochondrial morphology changes in response to CCCP-induced stress through open-source image processing software.
    Sudeshna Nag, Kaitlin Szederkenyi, Christopher M Yip, G Angus McQuibban.
      Mitochondrial morphology is an indicator of cellular health and function; however, its quantification and categorization into different subclasses is a complicated process. Here, we present a protocol for mitochondrial morphology quantification in the presence and absence of carbonyl cyanide m-chlorophenyl hydrazone stress. We describe steps for the preparation of cells for immunofluorescence microscopy, staining, and morphology quantification. The quantification protocol generates an aspect ratio that helps to categorize mitochondria into two clear subclasses. For complete details on the use and execution of this protocol, please refer to Nag et al.1.
    Keywords:  Cell Biology; Cell culture; Metabolism; Microscopy; Molecular/Chemical Probes
    DOI:  https://doi.org/10.1016/j.xpro.2023.102745
  2. Mitochondrion. 2023 Nov 29. pii: S1567-7249(23)00093-4. [Epub ahead of print]
    Understanding differential aspects of microdiffusion (channeling) in the Coenzyme Q and Cytochrome c regions of the mitochondrial respiratory system.
    Giorgio Lenaz, Salvatore Nesci, Maria Luisa Genova.
      Over the past decades, models of the organization of mitochondrial respiratory system have been controversial. The goal of this perspective is to assess this "conflict of models" by focusing on specific kinetic evidence in the two distinct segments of Coenzyme Q- and Cytochrome c-mediated electron transfer. Respiratory supercomplexes provide kinetic advantage by allowing a restricted diffusion of Coenzyme Q and Cytochrome c, and short-range interaction with their partner enzymes. In particular, electron transfer from NADH is compartmentalized by channeling of Coenzyme Q within supercomplexes, whereas succinate oxidation proceeds separately using the free Coenzyme Q pool. Previous evidence favoring Coenzyme Q random diffusion in the NADH-dependent electron transfer is due to downstream flux interference and misinterpretation of results. Indeed, electron transfer by complexes III and IV via Cytochrome c is less strictly dependent on substrate channeling in mammalian mitochondria. We briefly describe these differences and their physiological implications.
    Keywords:  Coenzyme Q or ubiquinone; Cytochrome c; channeling; diffusion; respiratory supercomplex
    DOI:  https://doi.org/10.1016/j.mito.2023.11.005
This page is being maintained by Thomas Krichel. It was last updated on 2024‒11‒22 at 4:28.