Search for directed genic interactions:  

MTOR ➞ FAS (1 - 2 of 2)
PMID: 20193134
High glucose induces differentiation and adipogenesis in porcine muscle satellite cells via mTOR. 		... and fatty acid synthase (FAS) protein ... gradually enhanced during ... while mTOR phosphorylation ...   (details)

MTOR ➞ FAS

Type:  positive regulation
Is this interaction correct?
Yes
No

Comments

PMID: 20193134

High glucose induces differentiation and adipogenesis in porcine muscle satellite cells via mTOR.
Source

BMB reports (February 2010)

Abstract

High glucose induces differentiation and adipogenesis in porcine muscle satellite cells via mTOR. The present study investigated whether the mammalian target of rapamycin (mTOR) signal pathway is involved in the regulation of high glucose-induced intramuscular adipogenesis in porcine muscle satellite cells. High glucose (25 mM) dramatically increased intracellular lipid accumulation in cells during the 10-day adipogenic differentiation period. The expressions of CCAAT/enhancer binding protein-alpha (C/EBP-alpha) and fatty acid synthase (FAS) protein were gradually enhanced during the 10-day duration while mTOR phosphorylation and sterol-regulatory-element-binding protein (SREBP)-1c protein were induced on day 4. Moreover, inhibition of mTOR activity by rapamycin resulted in a reduction of SREBP-1c protein expression and adipogenesis in cells. Collectively, our findings suggest that the adipogenic differentiation of porcine muscle satellite cells and a succeeding extensive adipogenesis, which is triggered by high glucose, is initiated by the mTOR signal pathway through the activation of SREBP-1c protein. This process is previously uncharacterized and suggests a cellular mechanism may be involved in ectopic lipid deposition in skeletal muscle during type 2 diabetes.

PMID: 23585690
Nutrient-dependent phosphorylation channels lipid synthesis to regulate PPARa. 		... of mammalian/mechanistic target of rapamycin complex... reduced FAS phosphorylation ...   (details)

MTOR ➞ FAS

Type:  positive regulation
Is this interaction correct?
Yes
No

Comments

PMID: 23585690

Nutrient-dependent phosphorylation channels lipid synthesis to regulate PPARa.
Source

Journal of lipid research (July 2013)

Abstract

Nutrient-dependent phosphorylation channels lipid synthesis to regulate PPARa. Peroxisome proliferator-activated receptor (PPAR) a is a nuclear receptor that coordinates liver metabolism during fasting. Fatty acid synthase (FAS) is an enzyme that stores excess calories as fat during feeding, but it also activates hepatic PPARa by promoting synthesis of an endogenous ligand. Here we show that the mechanism underlying this paradoxical relationship involves the differential regulation of FAS in at least two distinct subcellular pools: cytoplasmic and membrane-associated. In mouse liver and cultured hepatoma cells, the ratio of cytoplasmic to membrane FAS-specific activity was increased with fasting, indicating higher cytoplasmic FAS activity under conditions associated with PPARa activation. This effect was due to a nutrient-dependent and compartment-selective covalent modification of FAS. Cytoplasmic FAS was preferentially phosphorylated during feeding or insulin treatment at Thr-1029 and Thr-1033, which flank a dehydratase domain catalytic residue. Mutating these sites to alanines promoted PPARa target gene expression. Rapamycin-induced inhibition of mammalian/mechanistic target of rapamycin complex 1 (mTORC1), a mediator of the feeding/insulin signal to induce lipogenesis, reduced FAS phosphorylation, increased cytoplasmic FAS enzyme activity, and increased PPARa target gene expression. Rapamycin-mediated induction of the same gene was abrogated with FAS knockdown. These findings suggest that hepatic FAS channels lipid synthesis through specific subcellular compartments that allow differential gene expression based on nutritional status.