bims-smemid 2023-08-27 papers

Antioxidants (Basel). 2023 Aug 20. pii: 1644. [Epub ahead of print]12(8):

Regulation of Mitochondrial Respiration by Hydrogen Sulfide.

Dandan Huang, Guangqin Jing, Shuhua Zhu.

Hydrogen sulfide (H2S), the third gasotransmitter, has positive roles in animals and plants. Mitochondria are the source and the target of H2S and the regulatory hub in metabolism, stress, and disease. Mitochondrial bioenergetics is a vital process that produces ATP and provides energy to support the physiological and biochemical processes. H2S regulates mitochondrial bioenergetic functions and mitochondrial oxidative phosphorylation. The article summarizes the recent knowledge of the chemical and biological characteristics, the mitochondrial biosynthesis of H2S, and the regulatory effects of H2S on the tricarboxylic acid cycle and the mitochondrial respiratory chain complexes. The roles of H2S on the tricarboxylic acid cycle and mitochondrial respiratory complexes in mammals have been widely studied. The biological function of H2S is now a hot topic in plants. Mitochondria are also vital organelles regulating plant processes. The regulation of H2S in plant mitochondrial functions is gaining more and more attention. This paper mainly summarizes the current knowledge on the regulatory effects of H2S on the tricarboxylic acid cycle (TCA) and the mitochondrial respiratory chain. A study of the roles of H2S in mitochondrial respiration in plants to elucidate the botanical function of H2S in plants would be highly desirable.

Keywords: hydrogen sulfide; mitochondria; mitochondrial respiratory complex; oxidative phosphorylation; tricarboxylic acid cycle

DOI: https://doi.org/10.3390/antiox12081644

Trends Plant Sci. 2023 Aug 18. pii: S1360-1385(23)00238-8. [Epub ahead of print]

Promotion of oxidative phosphorylation by complex I-anchored carbonic anhydrases?

Hans-Peter Braun, Niklas Klusch.

The mitochondrial NADH-dehydrogenase complex of the respiratory chain, known as complex I, includes a carbonic anhydrase (CA) module attached to its membrane arm on the matrix side in protozoans, algae, and plants. Its physiological role is so far unclear. Recent electron cryo-microscopy (cryo-EM) structures show that the CA module may directly provide protons for translocation across the inner mitochondrial membrane at complex I. CAs can have a central role in adjusting the proton concentration in the mitochondrial matrix. We suggest that CA anchoring in complex I represents the original configuration to secure oxidative phosphorylation (OXPHOS) in the context of early endosymbiosis. After development of 'modern mitochondria' with pronounced cristae structures, this anchoring became dispensable, but has been retained in protozoans, algae, and plants.

Keywords: NADH dehydrogenase complex (complex I); Oxidative Phosphorylation (OXPHOS); carbonic anhydrase; endosymbiotic theory; mitochondria; mitochondrial evolution

DOI: https://doi.org/10.1016/j.tplants.2023.07.007

Ageing Res Rev. 2023 Aug 23. pii: S1568-1637(23)00197-6. [Epub ahead of print] 102038

Mitochondrial Transfer Between Cell Crosstalk - An Emerging Role in Mitochondrial Quality Control.

Yi Liu, Tinglv Fu, Guorui Li, Boyang Li, Guoqing Luo, Ning Li, Qing Geng.

Intercellular signaling and component conduction are essential for multicellular organisms' homeostasis, and mitochondrial transcellular transport is a key example of such cellular component exchange. In physiological situations, mitochondrial transfer is linked with biological development, energy coordination, and clearance of harmful components, remarkably playing important roles in maintaining mitochondrial quality. Mitochondria are engaged in many critical biological activities, like oxidative metabolism and biomolecular synthesis, and are exclusively prone to malfunction in pathological processes. Importantly, severe mitochondrial damage will further amplify the defects in the mitochondrial quality control system, which will mobilize more active mitochondrial transfer, replenish exogenous healthy mitochondria, and remove endogenous damaged mitochondria to facilitate disease outcomes. This review explores intercellular mitochondrial transport in cells, its role in cellular mitochondrial quality control, and the linking mechanisms in cellular crosstalk. We also describe advances in therapeutic strategies for diseases that target mitochondrial transfer.

Keywords: cell crosstalk; intercellular mitochondrial transfer; mitochondrial quality control; therapy

DOI: https://doi.org/10.1016/j.arr.2023.102038