mTOR Pathway
High mTOR = growth mode: hire aggressively, expand into new markets, burn capital to capture market share.
The hummingbird grows fast and burns bright for 3 years. The tortoise grows slow and lives 150 years. Same choice. Different timescale. Evolution gave you a switch, not a dial.
The mTOR pathway is evolution's fundamental choice: grow or maintain, reproduce or survive, live fast or live long. When calories are abundant, mTOR activates - protein synthesis accelerates, lipid synthesis ramps up, the cell prepares to divide. This is R-strategy: reproduce maximally, live fast, die young.
When calories drop, mTOR shuts down. Protein synthesis stops, cell division halts, autophagy activates, stress resistance pathways engage (FOXO and HSF1 transcription factors). This is K-strategy: survive until conditions improve, maintain, repair, wait.
Rapamycin - a bacterial metabolite that directly inhibits mTOR - extends lifespan across every organism tested: yeast 20% longer, worms 25% longer, flies 10-15% longer, mice 10-15% longer even when started late in life. The pattern is universal: suppress mTOR, extend life. Growth and longevity are antagonistic - you can't maximize both simultaneously.
Business Application of mTOR Pathway
High mTOR = growth mode: hire aggressively, expand into new markets, burn capital to capture market share. Low mTOR = maintenance mode: optimize existing products, focus on efficiency and profitability, extend runway. VC-backed startups operate in perpetual high-mTOR mode ('grow or die'), and 90% fail within 5 years. Bootstrapped companies can toggle between modes - grow when conditions are favorable, maintain when conditions are harsh.