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Mitochondrial numbers increase during glucose deprivation in the slime mold Physarum polycephalum.

ABSTRACT: Glucose deprivation in the slime mold Physarum polycephalum leads to a specific morphotype, a highly motile mesoplasmodium. We investigated the ultrastructure of both mesoplasmodia and non-starved plasmodia and found significantly increased numbers of mitochondria in glucose-deprived mesoplasmodia. The volume of individual mitochondria was the same in both growth forms. We conjecture that the number of mitochondria correlates with the metabolic state of the cell: When glucose is absent, the slime mold is forced to switch to different metabolic pathways, which occur inside mitochondria. Furthermore, a catabolic cue (such as AMP-activated protein kinase (AMPK)) could stimulate mitochondrial biogenesis.

SUBMITTER: Oettmeier C

PROVIDER: S-EPMC6820597 | biostudies-literature | 2019 Nov

REPOSITORIES: biostudies-literature

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Mitochondrial numbers increase during glucose deprivation in the slime mold Physarum polycephalum.

Oettmeier Christina C Döbereiner Hans-Günther HG

Protoplasma 20190702 6

Glucose deprivation in the slime mold Physarum polycephalum leads to a specific morphotype, a highly motile mesoplasmodium. We investigated the ultrastructure of both mesoplasmodia and non-starved plasmodia and found significantly increased numbers of mitochondria in glucose-deprived mesoplasmodia. The volume of individual mitochondria was the same in both growth forms. We conjecture that the number of mitochondria correlates with the metabolic state of the cell: When glucose is absent, the slim ...[more]

PMID: 31267225

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