Dataset Information

Regulation of autophagy and lipid accumulation under phosphate limitation in Rhodotorula toruloides.

ABSTRACT:

Background

It is known that autophagy is essential for cell survival under stress conditions. Inorganic phosphate (Pi) is an essential nutrient for cell growth and Pi-limitation can trigger autophagy and lipid accumulation in oleaginous yeasts, yet protein (de)-phosphorylation and related signaling events in response to Pi limitation and the molecular basis linking Pi-limitation to autophagy and lipid accumulation remain elusive.

Results

Here, we compared the proteome and phosphoproteome of Rhodotorula toruloides CGMCC 2.1389 under Pi-limitation and Pi-repletion. In total, proteome analysis identified 3,556 proteins and the phosphoproteome analysis identified 1,649 phosphoproteins contained 5,659 phosphosites including 4,499 pSer, 978 pThr, and 182 pTyr. We found Pi-starvation-induced autophagy was regulated by autophagy-related proteins, but not the PHO pathway. When ATG9 was knocked down, the engineered strains produced significantly less lipids under Pi-limitation, suggesting that autophagy required Atg9 in R. toruloides and that was conducive to lipid accumulation.

Conclusion

Our results provide new insights into autophagy regulation under Pi-limitation and lipid accumulation in oleaginous yeast, which should be valuable to guide further mechanistic study of oleaginicity and genetic engineering for advanced lipid producing cell factory.

SUBMITTER: Wang YN

PROVIDER: S-EPMC9908577 | biostudies-literature | 2022

REPOSITORIES: biostudies-literature

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Publications

Regulation of autophagy and lipid accumulation under phosphate limitation in <i>Rhodotorula toruloides</i>.

Wang Ya-Nan YN Liu Fang-Jie FJ Liu Hong-di HD Zhang Yue Y Jiao Xiang X Ye Ming-Liang ML Zhao Zong-Bao Kent ZK Zhang Su-Fang SF

Frontiers in microbiology 20230126

<h4>Background</h4>It is known that autophagy is essential for cell survival under stress conditions. Inorganic phosphate (Pi) is an essential nutrient for cell growth and Pi-limitation can trigger autophagy and lipid accumulation in oleaginous yeasts, yet protein (de)-phosphorylation and related signaling events in response to Pi limitation and the molecular basis linking Pi-limitation to autophagy and lipid accumulation remain elusive.<h4>Results</h4>Here, we compared the proteome and phosphop ...[more]

PMID: 36777022

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