The effects of Bax (full-length, FL, and C-terminal truncated, DeltaC) on respiration rate, membrane potential, MgATPase activity and kinetics of regulation of respiration were studied in isolated rat heart mitochondria and permeabilized cardiomyocytes. The results showed that while both Bax-FL and Bax-DeltaC permeabilized the outer mitochondrial membrane, released cytochrome c and reduced the respiration rate, the latter could be fully restored by exogenous cytochrome c only in the case of Bax-DeltaC, but not in presence of Bax-FL. In addition, Bax-FL but not Bax-DeltaC increased the MgATPase activity, and their effects on the mitochondrial membrane potential were quantitatively different. None of these effects was sensitive to cyclosporin A (CsA). It is concluded that Bax-FL affects both the outer and the inner mitochondrial membranes by: (1) opening large pores in the outer membrane; (2) inhibiting some segments of the respiratory chain in the inner membrane; and (3) uncoupling the inner mitochondrial membrane by increasing proton leak without opening the permeability transition pore (PTP).
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1016/s0005-2728(02)00358-4 | DOI Listing |
Cell Mol Life Sci
January 2025
Centro de Investigación en Sanidad Animal, Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria, Consejo Superior de Investigaciones Científicas (CISA-INIA-CSIC), Valdeolmos, Madrid, Spain.
Cyclic GMP-AMP synthase (cGAS) is a DNA sensing cellular receptor that induces IFN-I transcription in response to pathogen and host derived cytosolic DNA and can limit the replication of some RNA viruses. Some viruses have nonetheless evolved mechanisms to antagonize cGAS sensing. In this study, we evaluated the interaction between Bluetongue virus (BTV), the prototypical dsRNA virus of the Orbivirus genus and the Sedoreoviridae family, and cGAS.
View Article and Find Full Text PDFAdv Sci (Weinh)
January 2025
Department of Burns, Nanfang Hospital, Southern Medical University, Guangzhou, 510515, China.
Diabetic foot ulcer (DFU) is a common and severe complication of diabetes mellitus, the etiology of which remains insufficiently understood, particularly regarding the involvement of extracellular vesicles (EVs). In this study, nanoflow cytometry to detect EVs in DFU skin tissues is used and found a significant increase in the Translocase of Outer Mitochondrial Membrane 20 (TOM20) mitochondrial-derived vesicles (MDVs). The role of MDVs in DFU is yet to be reported.
View Article and Find Full Text PDFJ Eukaryot Microbiol
January 2025
Departmento de Parasitologia, Instituto de Ciências Biomédicas, Universidade de São Paulo (USP), São Paulo, SP, Brazil.
All insect trypanosomatids of the subfamily Strigomonadinae harbor a proteobacterial symbiont in their cytoplasm and unique ultrastructural cell organization. Here, we report an unexpected finding within the Strigomonadinae subfamily: the identification of a new species lacking bacterial symbiont, represented by two isolates obtained from Calliphoridae flies in Brazil and Uganda. This species is hereby designated as Kentomonas inusitatus n.
View Article and Find Full Text PDFFront Vet Sci
January 2025
Farm Animal Genetic Resources Exploration and Innovation Key Laboratory of Sichuan Province, College of Animal Science and Technology, Sichuan Agricultural University, Chengdu, China.
The motility of sperm decreases following cryopreservation, which is closely associated with mitochondrial function. However, the alterations in mitochondrial metabolism after sperm freezing in goats remain unclear. This experiment aimed to investigate the impact of ultra-low temperature freezing on goat sperm's mitochondrial energy metabolism and its potential correlation with sperm motility.
View Article and Find Full Text PDFiScience
January 2025
Centre Armand-Frappier Santé Biotechnologie, Institut National de la Recherche Scientifique, Laval, Québec H7V 1B7, Canada.
During infection, dengue virus (DENV) and Zika virus (ZIKV), two (ortho)flaviviruses of public health concern worldwide, induce alterations of mitochondria morphology to favor viral replication, suggesting a viral co-opting of mitochondria functions. Here, we performed an extensive transmission electron microscopy-based quantitative analysis to demonstrate that both DENV and ZIKV alter endoplasmic reticulum-mitochondria contact sites (ERMC). This correlated at the molecular level with an impairment of ERMC tethering protein complexes located at the surface of both organelles.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!