Calcium binding to a remote site can replace magnesium as cofactor for mitochondrial Hsp90 (TRAP1) ATPase activity.

ABSTRACT: The Hsp90 molecular chaperones are ATP-dependent enzymes that maintain protein homeostasis and regulate many essential cellular processes. Higher eukaryotes have organelle-specific Hsp90 paralogs that are adapted to each subcellular environment. The mitochondrial Hsp90, TNF receptor-associated protein 1 (TRAP1), supports the folding and activity of electron transport components and is increasingly appreciated as a critical player in mitochondrial signaling. Calcium plays a well-known and important regulatory role in mitochondria where it can accumulate to much higher concentrations than in the cytoplasm. Surprisingly, we found here that calcium can replace magnesium, the essential enzymatic cofactor, to support TRAP1 ATPase activity. Anomalous X-ray diffraction experiments revealed a calci

SUBMITTER: Elnatan D 

PROVIDER: S-EPMC6120219 | biostudies-literature | 2018 Aug

REPOSITORIES: biostudies-literature