Which of the following amino acids is a key regulator of the mTOR signaling pathway, which controls protein synthesis in response to nutrient availability?

A Leucine ✓
B Glutamine
C Arginine
D Lysine

Explanation

Leucine is a branched-chain amino acid that activates the mTOR signaling pathway, which regulates protein synthesis in response to nutrient availability.

Mnemonic

Leucine = 'lock' → locks onto mTOR pathway to regulate protein synthesis

Source

Kimball et al. (2010) Journal of Nutrition
Protein Metabolism Biochemistry Protein Synthesis Regulation Hard MEDICAL Confidence: medium