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Endoplasmic reticulum stress and calcium imbalance are involved in cadmium-induced lipid aberrancy in Saccharomyces cerevisiae.

ABSTRACT: The endoplasmic reticulum is the key organelle which controls protein folding, lipid biogenesis, and calcium (Ca(2+)) homeostasis. Cd exposure in Saccharomyces cerevisiae activated the unfolded protein response and was confirmed by the increased Kar2p expression. Cd exposure in wild-type (WT) cells increased PC levels and the PC biosynthetic genes. Deletion of the two phospholipid methyltransferases CHO2 and OPI3 modulated PC, TAG levels and the lipid droplets with cadmium exposure. Interestingly, we noticed an increase in the calcium levels upon Cd exposure in the mutant cells. This study concluded that Cd interrupted calcium homeostasis-induced lipid dysregulation leading to ER stress.

SUBMITTER: Rajakumar S

PROVIDER: S-EPMC5003806 | biostudies-other | 2016 Sep

REPOSITORIES: biostudies-other

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Endoplasmic reticulum stress and calcium imbalance are involved in cadmium-induced lipid aberrancy in Saccharomyces cerevisiae.

Rajakumar Selvaraj S Bhanupriya Nagaraj N Ravi Chidambaram C Nachiappan Vasanthi V

Cell stress & chaperones 20160625 5

The endoplasmic reticulum is the key organelle which controls protein folding, lipid biogenesis, and calcium (Ca(2+)) homeostasis. Cd exposure in Saccharomyces cerevisiae activated the unfolded protein response and was confirmed by the increased Kar2p expression. Cd exposure in wild-type (WT) cells increased PC levels and the PC biosynthetic genes. Deletion of the two phospholipid methyltransferases CHO2 and OPI3 modulated PC, TAG levels and the lipid droplets with cadmium exposure. Interestingl ...[more]

PMID: 27344570

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