Biochemical controls: mitochondrial vast activities (Introduction)

by David Turell , Monday, January 08, 2024, 19:04 (318 days ago) @ David Turell

Exert many different effects:

https://www.the-scientist.com/the-literature/rebranding-mitochondria-71490?utm_campaign...

"Picard and Orian Shirihai, a mitochondrial biologist at the University of California, Los Angeles, made the case that the powerhouse analogy is dated; they instead focus on the organelle as the great communicator of the cell.1 “Mitochondria function like cellular processors, like little antennas that can receive information, integrate information, and then produce signals that influence the cell and the whole organism,” said Picard. Inputs include hormones, metabolites, and nutrients that direct output signals that orchestrate metabolic pathways, gene expression, and drive adaptive behaviors.

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"Picard noted rising evidence of mitochondrial phenotypes, or mitotypes, that likely influence signal processing and mitochondrial communication.3 For example, Picard’s team and others showed that brain cells in mice exhibit regional and cell-specific functional differences, while human immune cells vary in ATP production and mitochondrial DNA copy number.

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"In their Nature Metabolism perspective, Picard and his colleagues proposed a terminology system to increase specificity in the language of mitochondrial science.2 Their system distinguishes between the multitude of cell-dependent properties, molecular features, activities, functions, and behaviors employed by mitochondria.

"Mike Murphy, a mitochondrial biologist at the University of Cambridge who was not involved with writing the perspectives, agreed with Picard’s call for more precise language. “We’re using vague terms like mitochondrial dysfunction, and it’s not clear what that means,” said Murphy. Instead, descriptions should focus on the specific process that has gone awry, such as calcium homeostasis, oxidative phosphorylation producing ATP, or contributions to immune signaling. “With a greater understanding of the many roles of mitochondria, the more precise you can be and the better and clearer the hypothesis you’ll come up with will be,” said Murphy.

“'I’m supportive of the goal, [but] I’m reluctant to go along with a rigid nomenclature,” said Murphy. Mitochondria are dynamic and constantly adapting in response to a changing environment, which could make it difficult to pigeonhole these shapeshifting organelles into one classification over another.

"Whether scientists adopt the proposed terminology system remains to be seen, but appreciation of the organelles’ incredible diversity is only growing. “In the world of mitochondrial biology, we’re in the same place as probably 200 years ago, when people realized ‘ooh, we’re made of cells,’” said Picard."

Comment: since mitochondria started out as independent organisms their activities are not surprising.