In the citric acid (TCA) cycle, accumulation of which intermediate can allosterically inhibit phosphofructokinase-1 and thus slow glycolysis?
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Correct answer: Citrate exported to the cytosol
Citrate, exported from the mitochondria when TCA cycle intermediates accumulate, acts as an allosteric inhibitor of PFK-1 — signaling that energy and biosynthetic precursors are abundant and decreasing glycolytic flux.
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