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bioRxiv · 10.1101/2024.06.28.601304

PINK1-G411S mutant increases kinase stability and enhances mitochondrial-linked functions

Abstract

PINK1, a mitochondria targeted Serine/Threonine kinase, regulates ATP production by phosphorylating the Complex I subunit NdufA10. However, when in the presence of depolarized mitochondria, PINK1 phosphorylates ubiquitin and Parkin triggering mitochondria clearance. Mutations in PINK1 have been linked to early-onset recessive familial forms of Parkinsons disease (PD). Deficits in Complex I enzymatic activity and an increase in oxidative damage have been identified in multiple brain regions of PD patients. Unravelling how PINK1 activity regulates mitochondria fate is pivotal. In the present study we characterized how human PD-related PINK1 mutants affect major PINK1 functions. Using molecular dynamics, we gain mechanistic insight into how specific mutations alter the tertiary structure and stability of PINK1s ATP-binding pocket, leading to an increased rigidity and stability. More importantly, we report a structural explanation for the enhanced kinase function of the PINK1-G411S mutant.

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BibTeXRIS

Goncalves, F. B., Enguita, F. J., Morais, V. A.. 2024-07-01. PINK1-G411S mutant increases kinase stability and enhances mitochondrial-linked functions. https://doi.org/10.1101/2024.06.28.601304

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