BAG3 promotes autophagy and glutaminolysis via stabilizing glutaminase.

Bcl-2 associated athanogene 3 (BAG3) is an important molecule that maintains oncogenic features of cancer cells via diverse mechanisms. One of the important functions assigned to BAG3 is implicated in selective macroautophagy/autophagy, which attracts much attention recently. However, the mechanism underlying regulation of autophagy by BAG3 has not been well ...
defined. Here, we describe that BAG3 enhances autophagy via promotion of glutamine consumption and glutaminolysis. Glutaminolysis initiates with deamination of glutamine by glutaminase (GLS), by which yields glutamate and ammonia in mitochondria. The current study demonstrates that BAG3 stabilizes GLS via prohibition its interaction with SIRT5, thereby hindering its desuccinylation at Lys158 and Lys164 sites. As an underlying molecular mechanism, we demonstrate that BAG3 interacts with GLS and decreases SIRT5 expression. The current study also demonstrates that occupation by succinyl at Lys158 and Lys164 sites prohibits its Lys48-linked ubiquitination, thereby preventing its subsequent proteasomal degradation. Collectively, the current study demonstrates that BAG3 enhances autophagy via stabilizing GLS and promoting glutaminolysis. For the first time, this study reports that succinylation competes with ubiquitination to regulate proteasomal GLS degradation.
Mesh Terms:
Adaptor Proteins, Signal Transducing, Ammonia, Apoptosis Regulatory Proteins, Autophagy, Enzyme Stability, Glutaminase, Glutamine, Hep G2 Cells, Humans, MCF-7 Cells, Mitochondria, Neoplasms, Proteasome Endopeptidase Complex, Proteolysis, Sirtuins, Transfection, Ubiquitination
Cell Death Dis
Date: Mar. 25, 2019
Download Curated Data For This Publication
242999
Switch View:
  • Interactions 2