Yeast perilipin Pet10p/Pln1p interacts with Erg6p in ergosterol metabolism

Martina Garaiova; Yunfeng Ding; Roman Holic; Martin Valachovic; Congyan Zhang; Ivan Hapala; Pingsheng Liu

doi:10.1016/j.bbalip.2024.159506

Yeast perilipin Pet10p/Pln1p interacts with Erg6p in ergosterol metabolism

Biochim Biophys Acta Mol Cell Biol Lipids. 2024 May 9;1869(6):159506. doi: 10.1016/j.bbalip.2024.159506. Online ahead of print.

Authors

Martina Garaiova¹, Yunfeng Ding², Roman Holic³, Martin Valachovic³, Congyan Zhang², Ivan Hapala³, Pingsheng Liu⁴

Affiliations

¹ Department of Biochemistry of Biomembranes, Institute of Animal Biochemistry and Genetics, Centre of Biosciences, Slovak Academy of Sciences, Dubravska cesta 9, Bratislava 840 05, Slovakia. Electronic address: martina.garaiova@savba.sk.
² National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China.
³ Department of Biochemistry of Biomembranes, Institute of Animal Biochemistry and Genetics, Centre of Biosciences, Slovak Academy of Sciences, Dubravska cesta 9, Bratislava 840 05, Slovakia.
⁴ National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China; University of Chinese Academy of Sciences, Beijing 100049, China. Electronic address: pliu@ibp.ac.cn.

PMID: 38734059
DOI: 10.1016/j.bbalip.2024.159506

Abstract

Lipid droplets (LD) are highly dynamic organelles specialized for the regulation of energy storage and cellular homeostasis. LD consist of a neutral lipid core surrounded by a phospholipid monolayer membrane with embedded proteins, most of which are involved in lipid homeostasis. In this study, we focused on one of the major LD proteins, sterol C24-methyltransferase, encoded by ERG6. We found that the absence of Erg6p resulted in an increased accumulation of yeast perilipin Pet10p in LD, while the disruption of PET10 was accompanied by Erg6p LD over-accumulation. An observed reciprocal enrichment of Erg6p and Pet10p in pet10Δ and erg6Δ mutants in LD, respectively, was related to specific functional changes in the LD and was not due to regulation on the expression level. The involvement of Pet10p in neutral lipid homeostasis was observed in experiments that focused on the dynamics of neutral lipid mobilization as time-dependent changes in the triacylglycerols (TAG) and steryl esters (SE) content. We found that the kinetics of SE hydrolysis was reduced in erg6Δ cells and the mobilization of SE was completely lost in mutants that lacked both Erg6p and Pet10p. In addition, we observed that decreased levels of SE in erg6Δpet10Δ was linked to an overexpression of steryl ester hydrolase Yeh1p. Lipid analysis of erg6Δpet10Δ showed that PET10 deletion altered the composition of ergosterol intermediates which had accumulated in erg6Δ. In conclusion, yeast perilipin Pet10p functionally interacts with Erg6p during the metabolism of ergosterol.

Keywords: ERMES; Lipid droplets; Lipids; Mitochondria; Proteomics; Sterols; Steryl esters; Triacylglycerols.