Fig. 4: Glycolysis from uridine bypasses the regulated steps of upper glycolysis and supports OXPHOS-deficient cells.
From: Salvage of ribose from uridine or RNA supports glycolysis in nutrient-limited conditions
a, Schematic of glycolysis inhibition by OXPHOS. G6P, glucose-6-phosphate. b, Representative ECAR in UPP1-expressing K562 cells grown in sugar-free medium with and without supplementation of 10 mM of glucose, galactose or uridine, with n = 30 replicate wells. O, oligomycin; C, CCCP; A, antimycin A. Data are shown as the mean ± s.d. c, 13C5-uridine tracer analysis reporting intracellular lactate in UACC-257 melanoma cells in glucose-free RPMI medium containing 5 mM 13C5-uridine and in competition with increasing amount of unlabelled glucose (0, 1, 5, 10 and 25 mM) or treated with 100 nM antimycin A, all after 5 h (n = 4, P < 1.7 × 10−4, P < 4.9 × 10−3, P < 1.8 × 10−5, P < 5.9 × 10−5, P > 0.05). Data are shown as the mean ± s.e.m. and are corrected for natural isotope abundance. P values were calculated using a two-sided Student’s t-test. Statistics were not adjusted for multiple comparisons. d, Percentage of dead cells in UPP1-expressing K562 cells grown in 5 mM glucose or galactose supplemented with 5 mM uridine (U) and antimycin A (anti. A). Data are shown as the mean ± s.e.m. with two-sided t-test relative to control K562 cells (n = 4, P < 3.9 × 10−5).
