External ID: HMS1262

Protocol: NEC is stored at -80 degrees at a concentration of 15mg/ml in single use aliquots.

On the day of the screen, 20ul of purified NEC is aliquoted using a Multidrop Combi reagent dispenser into 384 well plates (Corning 3824). 100nl of compound dissolved in DMSO was transferred to each well of the assay plated via pin transfer. The plates (NEC + compound) are incubated at room temperature for 3 hours. Acceptor and donor reagents (CisBio 620/665 pair) are combined then added to each well at 5 microL volumes at a concentration of 8 nM and 80nM respectively. The plates are spun at 1k rpm for 1 min and incubated overnight at 4 degrees, then for one hour the subsequent day at room temperature.

Flourescent measurements are read on the Envision 1 plate reader at ICCB-L. The raw data consists of two fluorescence readings - at 665 nm and 620 nm for the acceptor and donor respectively.

Comment: Data analysis:
The raw data consists of two fluorescence readings - at 665 and 620 nm for the acceptor and donor respectively. The data is processed as a ratio of the emission from the acceptor over the donor (homogeneous time resolved fluorescence ratio). Normalized percent inhibition (NPI) for all experimental wells is calculated based on plate averages for negative and positive control HTRF ratio. Positives are scored as any ratio with a 50% or greater inhibition as compared with the positive control (i.e. NEC + Untagged UL50). To be considered a hit, both replicates need to score as positive. Activity scores are derived from NPI, with 100 = 100% inhibition (> 100% set to 100) and 0 = no inhibition (< 0% set to 0). Note that some compounds with NPI <50% (activity scores < 50) are classified as potential hits based on additional criteria (typically by selecting wells with low ratios compared to other experimental wells on the plate).

External ID: HMS1482

Protocol: Prior to screening, cells were passaged in high glucose DMEM supplemented with 10% FBS, 1% P/S, 1 mM pyruvate, and HEPES. Media was changed every 1-2 days to prevent starvation and maintain cellular health.

On the day of screening, 384-well plates (Corning 3765) were filled with 30 uL of control cybrid cell suspension (33.3 cells/ul). Media for resuspension was DMEM supplemented with 10% FBS, 1% P/S, 1 mM pyruvate, and HEPES. Positive control columns were 23 and 24 for most plate setups. Initially, tunicamycin (15 nM) and galactose media (10 mM + 1 mM glucosamine) were used in columns 23 and 24, respectively. Over the course of the screen, galactose was substituted with Vidofludimus (11 uM). Next, 33 nL of each compound were pin-transferred to each plate in duplicate. Final assay well volume was 30 uL. Plates were stacked 2 high, covered with lids, and incubated at 37 degrees C for 2 days.

After 2 days of incubation, Hoescht (10 ul/well) was added to assay plates and fluorescence was read using the Acumen laser scanning cytometer. After, the bottom of plates were sealed with two layers of Brightmax Sealing Films. Then Promega NanoGlo Live cell reagent (20 ul/well) was added to each well and luminescence was read on a PerkinElmer EnVision plate reader after 5 minute of shaking.

Comment: Data analysis method and criteria for scoring active compounds:

Normalized luminescence values (luminescence / cell number) for each replicate were calculated (based on average of 2 luminescence reads per replicate). Z-scores were calculated using the plate average and standard deviation of experimental well normalized values. Each plate replicate was individually analyzed to measure reproducibility across plates. Z-scores were then averaged across replicates and a Z-score threshold of 1.96 was selected for positive hits, indicating increased mitochondrial supercomplex formation. Wells were excluded from further consideration based on low cell number (1 or both replicates with number of objects count < 1500). Activity scores were determined by scaling Z-scores from 0 (activity score = 0) to 4 (activity score = 100), with activity score > 50 being considered active. Z-scores < 0 were set to activity score = 0; Z-scores > 4 were set to activity score = 100 (100% activity).

External ID: HMS1485

Protocol: Prior to screening, HeLa cells were transduced with a lentivirus carrying the vector PHAGE-N CMVt N-RIG3 p53(R273C) encoding constitutively expressed SGFP2 fused to histone 2B and mRuby-p53(R273C). Following transduction, the cells were selected using neomycin and fluorescent activated cell sorting. The day before the compound treatment, cells were plated (750 cells/well) in a final volume of 30 L/well of Dulbecco's modified Eagle's medium (DMEM) supplemented with 10% (v/v) fetal bovine serum using a Thermo Combi. Plates were spun for 45 s at 500 rpm and incubated overnight (~24 h) at 37 degrees C, 5% CO2.

On the day of the screening, 33 nL of each compound was transferred to assay wells via a custom pin-transfer workstation. Additionally, 33 nL of positive (Velcade 300 M) and negative (DMSO 100%) controls were transferred to each plate into the corresponding columns that did not contain experimental compounds. For every compound library plate, there were two daughter plates (A and B). Plates were stacked 5 high, covered with lids, and incubated at 37 degrees C for 24h and 48h.

Assay plates were read using an Acumen Laser Scanning Cytometer 24h and 48h after compound treatment, using the following settings: For SGFP2 (channel 2), the 488 nm laser was used, with 6 mW output, 600 voltage gain and sensitivity threshold at 1; and for mRuby (channel 3), the 561 nm laser was used, with 8 mW output, 600 voltage gain and sensitivity threshold at 1.

Comment: Total nuclei and %p53 positive was calculated for all wells at 24 and 48h using the Cellista software. Percentage of p53 positive cells values were normalized to the positive and negative controls to determine a normalized percent of p53 activation. This was done on a per plate basis. The proteasome inhibitor Velcade (Adipogen, AG-CR1-3602-M005) at 330 nM was used as positive control while only the vehicle (DMSO, Sigma, D8418, 0.1% final concentration) was used as negative control. From these values the following normalized values were calculated (for both 24h and 48h): Normalized total nuclei = (total nuclei in experimental well / plate average negative control total nuclei) * 100. Normalized %p53 positive = (%p53 positive in experimental well - plate average negative control %p53 positive cells) / (plate average positive control %p53 positive cells - plate average negative control %p53 positive cells) * 100.

Based on the normalized percent p53 positive values, a compound was considered active when replicate average normalized % p53 positive cells > 50% for either or both time points. Activity scores were based on the replicate average normalized %p53 positive cells at 24hr. Values less than 0 were set to 0, and values > 100 were set to 100 (100% activity). Compounds with an activity score > 50 were considered active; some compounds were scored active despite having an activity score < 50 since % p53 positive cells was > 50% only at 48hr.

The average normalized total nuclei values were categorized as:
Very Low: x < 25%
Low: 25% < X > 50%
Medium: 50% < X > 75%
High: x < 75%

The average normalized % of p53 positive cells values were categorized as:
Low: x < 25%
Medium: 25% < X > 50%
Strong: 50% < X > 75%
Very Strong: x < 75%

Compounds that scored as strong or very strong in this classification (at either time point) were selected for follow up.