Journal: The FASEB Journal

Article Title: Elucidating the Molecular Impact of DA29‐Induced ClpP Chemoactivation on Mitochondrial Function

doi: 10.1096/fj.202603398RR

Figure Lengend Snippet: Targeted activation of endogenous mitochondrial ClpP. (A) Western blots of mitochondrial lysates (30 μg) from wild‐type and ClpP‐KO HEK293T cells were probed with antibodies against ClpP and α‐tubulin, the latter being used as a loading control. (B) Analysis of ClpP and ClpX assembly was carried out in wild‐type HEK293T mitochondria through isokinetic sucrose gradient centrifugation. Mitochondrial lysate (0.65 mg) was centrifuged on a 10%–30% gradient using the SW 60Ti rotor at 40 000 rpm for 2 h and 15 min at 4°C. Small and large mitoribosomal subunits were used as a reference of migration and were immunodecorated by antibodies against marker proteins of the mt‐SSU (mS29; HUGO protein name: DAP3) and the mt‐LSU (uL13m; HUGO protein name: MRPL13). (C) Effect of ONC201‐mediated ClpP activation on casein hydrolysis in the PAGE‐based fluorescent assay. Mitochondrial lysates (50 μg) from wild‐type and KO cells were used as a source of ClpP activity, and incubated with ONC201 at a final concentration of 100 μM. Upper panels: Milk casein isoforms (α, β and k) are depicted to the left; molecular weight markers (M; Precision Plus Protein Dual Color Standards, Bio‐Rad) are indicated to the right. Middle panels: Total densitometric profile of fluorescent substrate was determined for each lane. Lower panels: Coomassie blue staining (CBS) of mitochondrial proteins was used as a loading control. (D) Chemical structure of DA29 (ClpP activator) and DA28 (negative control). (E) Effect of ClpP chemoactivation by DA29 on casein hydrolysis in the PAGE‐based fluorescent assay; DA28 was used as a negative control. For description, see panel C.

Article Snippet: Total cellular DNA was isolated by standard phenol‐extraction and mtDNA relative levels were measured by real‐time qPCR using the SsoAdvanced Universal SYBR Green Supermix (Bio‐Rad) and the Applied Biosystems 7500 Fast Real‐Time PCR System (Thermo Fisher Scientific).

Techniques: Activation Assay, Western Blot, Control, Analysis, Gradient Centrifugation, Migration, Marker, Fluorescence, Activity Assay, Incubation, Concentration Assay, Molecular Weight, Staining, Negative Control