Fig 2: SIRT2-7 protein levels in aging rat retinal neurons. Representative western blots showing the protein levels for SIRT2 (A), SIRT3 (B), SIRT4 (C), SIRT5 (D), SIRT6 (E) and SIRT7 (F) in the retinas of young, adult, and old rats. The histograms in each panel show the densitometric mean and SEM normalized to the corresponding level of the loading control protein β-Tubulin (∗P < 0.05, n = 4 independent subjects).

Fig 3: HFHFD differentially altered sirtuins gene expressions in the liver. Fold change of gene expression of (A) Sirt1, (B) Sirt2, (C) Sirt3, (D) Sirt4, (E) Sirt5, (F) Sirt6, and (G) Sirt7 in livers of LFD-, HFD-, and HFHFD-fed mice. Gene expression was normalized to β-actin. n = 7–8, * p < 0.05, ** p < 0.01 compared to LFD group. # p < 0.05 compared to HFD group. $ p < 0.05 with Student’s t-test compared to LFD group.

Fig 4: Protein-ligand interaction. 3D view of ligand fit into the binding pocket of the protein. The ligands bound to the active site of the protein are shown. (A) Sirt1, (B) Sirt2, (C) Sirt6, (D) Sirt3, (E) Sirt7, and (F) Sirt5.

Fig 5: Direct interaction between Dicer and SIRT7. (A) Co-IP of endogenous Dicer and SIRT7 in HEK293T and HCT116 cells using anti-Dicer antibody. (B) Co-IP of endogenous Dicer and SIRT7 using two different anti-SIRT7 antibodies (H00051547-D01 and 5360). (C) Anti-SIRT7 (5360) co-IP using HCT116 cell lysate in the presence of increasing NaCl concentrations. (D) Anti-SIRT7 (5360) co-IP using HCT116 cell lysate in the presence or absence of RNases. (E) Direct interaction of Dicer and SIRT7 revealed by co-IP using purified recombinant Dicer and SIRT7 proteins. The recombinant proteins and IP antibodies added in each reaction are indicated on the top. BSA was used to compensate the missing protein when only one protein (Dicer or SIRT7) was included in the assay. (F) Interaction between recombinant human Dicer protein and purified His-tagged SIRT7 protein revealed by in vitro binding assay. The proteins loaded to the His-tag purification column are indicated on the top. B, representative bound fraction, UB, representative unbound fraction. (G) Anti-FLAG M2 gel pulled down endogenous Dicer in extracts of stable Flag-SIRT7(WT)- or Flag-SIRT7 (S111A)-expressing HEK293T cells, but not in extracts of Flag-SIRT7(dE2)-expressing HEK293T cells. Ctr: HEK293T cells transfected with the empty vector pcDNA3.1.