Is There a Connection Between Life's Origin, Geothermal Vents, Cancer, and Aging?

Long-time Slashdot reader Beeftopia writes:All living cells power themselves by coaxing protons from one side of a membrane to the other. A place where this occurs naturally outside of cells are alkaline hydrothermal vents on the deep seafloor, inside highly porous rock formations that are almost like mineralized sponges. "Carbon and energy metabolism are driven by proton gradients, exactly what the vents provided for free," wrote biochemist Nick Lane. In Lane's view, metabolism came first, and genetic information emerged naturally from it rather than the other way around. Quanta magazine asks Lane the big question: How did these first proto-cells become independent from the proton gradients they got for free in the hydrothermal vents? LANE: We've shown that theoretically, if you introduce random sequences of RNA and assume that the nucleotides in there can polymerize, you get little chains of nucleotides. Let's say seven or eight random letters long, with no information encoded in there whatsoever.... [H]ydrophobic amino acids are more likely to interact with hydrophobic bases. So you have a random sequence of RNA that generates a nonrandom peptide. And that nonrandom peptide could by chance have some function in a growing proto-cell. It could make the cell grow better or grow worse; it could help the RNA replicate itself; it could bind to cofactors. Then you have selection for that peptide and the RNA sequence that gave rise to it. Although it's a very rudimentary system, this means we've just entered the world of genes, information and natural selection. Quanta summarizes Lane's next idea: that these vent environments "favored the beginnings of what we call the Krebs cycle, the metabolic process that derives energy from carbohydrates, fats and proteins." Lane himself has said that metabolism "conjures genes into existence." But if genes are conjured into existence by metabolism, then what else might be true? Lane ultimately concludes that cancer may be a metabolic disease rather than a "genomic" one: LANE: About 10 years ago, the cancer community was amazed by the discovery that in some cancers, mutations can lead to parts of the Krebs cycle running backward. It came as quite a shock because the Krebs cycle is usually taught as only spinning forward to generate energy. But it turns out that while a cancer cell does need energy, what it really needs even more is carbon-based building blocks for growth. So the whole field of oncology began to see this reversal of the Krebs cycle as a kind of metabolic rewiring that helps cancer cells grow.... [C]ancers aren't caused simply by some genetically deterministic mutation that forces cells to go on growing without stopping. Metabolism is important too, for providing a permissive environment for growth. Growth comes before genes in this sense. Or, as Slashdot reader Beeftopia puts it, "In Lane's view, metabolism came first, and genetic information emerged naturally from it rather than the other way around. Lane believes that the implications of this reversal touch almost every big mystery in biology, including the nature of cancer and aging."

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