Negative regulation of amino acid signaling by MAPK-regulated 4F2hc/Girdin complex.
Amino acid signaling mediated by the activation of mechanistic target of rapamycin complex 1 (mTORC1) is fundamental to cell growth and metabolism. However, how cells negatively regulate amino acid signaling remains largely unknown. Here, we show that interaction between 4F2 heavy chain (4F2hc), a s...
| Main Authors: | , , , , , , , , , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
Public Library of Science (PLoS)
2018-03-01
|
| Series: | PLoS Biology |
| Online Access: | https://doi.org/10.1371/journal.pbio.2005090 |
| Summary: | Amino acid signaling mediated by the activation of mechanistic target of rapamycin complex 1 (mTORC1) is fundamental to cell growth and metabolism. However, how cells negatively regulate amino acid signaling remains largely unknown. Here, we show that interaction between 4F2 heavy chain (4F2hc), a subunit of multiple amino acid transporters, and the multifunctional hub protein girders of actin filaments (Girdin) down-regulates mTORC1 activity. 4F2hc interacts with Girdin in mitogen-activated protein kinase (MAPK)- and amino acid signaling-dependent manners to translocate to the lysosome. The resultant decrease in cell surface 4F2hc leads to lowered cytoplasmic glutamine (Gln) and leucine (Leu) content, which down-regulates amino acid signaling. Consistently, Girdin depletion augments amino acid-induced mTORC1 activation and inhibits amino acid deprivation-induced autophagy. These findings uncovered the mechanism underlying negative regulation of amino acid signaling, which may play a role in tightly regulated cell growth and metabolism. |
|---|---|
| ISSN: | 1544-9173 1545-7885 |