(A) Relative Sirt4 mRNA levels in lung tissues for the indicated times after whole-body IR (10 Gy) were determined by qRT-PCR (n = 3). β-Actin was used as an endogenouse control for qRT-PCR.
(B) GDH activity in lung tissue extracts from WT and SIRT4 KO mice (n = 5 animals/genotype).
(C) GDH activity in lung tissue extracts from WT (left) and SIRT4 KO (right) mice at 12 hr after whole-body IR (10 Gy) (n = 5–6 mice of each condtion).
(D and E) Glutamine (D) and glucose (E) uptake in SIRT4 KO lung tumor cells reconstituted with SIRT4 (n = 3).
(F) Chromosomal abnormalities were examined in SIRT4 KO lung tumor cells reconstituted with SIRT4 after IR (5 Gy) treatment.
(G) A proposed model illustrating the regulation of metabolic response to DNA damage by SIRT4.
Data are means ±SEM. n.s., not significant. *p < 0.05, **p < 0.005. See also Figure S7.