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: RMI-FANCM-MM2

Protocol: FP HTS. Screening took place at the University of Wisconsin Small Molecule Screening and Synthesis Facility. A master mix of RMI core complex and F-MM2 (30 microL per well) was plated in black 384 shallow well plates (ThermoFisher, Waltham, MA), using a BioTek "MicroFlo Select" reagent dispenser. Compounds were added using a Beckman FX liquid handler; 0.33 microL of 10 mM stock was added for a final compound concentration of 33 microM. MM2 and cMM2 were each added to 4 wells of master mix per plate to a final concentration of 10 muM to serve as controls. Following compound addition, plates were covered, centrifuged briefly, and incubated for 20 minutes at room temperature. FP measurements were taking using a Tecan "Safire 2" microplate reader. Instrument settings were as follows: top read, EX 470, EM 525/20, G-factor 0.89947. A suitable gain was calculated from the first plate of each day. Z' scores for were calculated for each plate; plates with Z' scores <0.5 were rerun prior to analysis.

Comment:

External ID: MTASE-p

Protocol: PROTOCOL TABLE (as described by Inglese J, Shamu CE and Guy RK. 2007)
SEQUENCE No. (e.g., 1, 2, 3, etc.); PARAMETER (e.g., Cells, Incubation, Reagent, etc.); VALUE; DESCRIPTION.
1; Reagent; 2 uL; SMMTase Enzyme (2x) in reaction buffer, columns 1- 48.
2; Reagent; 1 uL; SAM (4x) in reaction buffer, columns 1-48.
3; Controls; 23 nL; DMSO in column 4; sinefungin in DMSO (0 uM - 40 uM) in 7-point 1:2 dilution series (n = 2) in column 2.
4; Compounds; 23 nL; Columns 5-48.
5; Reagent; 1 uL; Substrate (4x) in reaction buffer, columns 2-48.
6; Time; 20-30 min; Incubation.
7; Reagent; 1 uL; MTase-Glo reagent (5X), columns 1-48.
8; Time; 30 min; Incubation.
9; Reagent; 5 uL; MTase-Glo Detection reagent, columns 1-48.
10; Time; 30 min; Incubation, luminescence evolution.
11; Detection; Luminescence; ViewLux uHTS Microplate Imager (PerkinElmer).

NOTES (numbers refer to Sequence numbers above)
1, 2, 5. White Medium Binding Greiner 1536-well plates (Cat #789175-F, Greiner Bio-One, Monroe, NC); Reaction buffer: 50 mM Tris, pH 8.0, 3 mM MgCl2, 1 mM EDTA, 50 mM NaCl, 1 mM DTT, and 0.1 mg/mL BSA. Evaporation was prevented by covering assay plates with metal lids containing holes to allow gas diffusion.
1. Six SMMTase were profiled: HNMT, GNMT, PNMT, COMT, NNMT, GAMT
2. The corresponding SAM cofactor concentration was used for each SMMTase: HNMT - 9.3 uM SAM; GNMT - 12.1 uM SAM; PNMT - 3.6 uM SAM; COMT - 14.5 uM SAM; NNMT 11.9 uM SAM; GAMT - 5.6 uM SAM.
3, 4. Pintool transfer
5. The corresponding substrate was used for each enzyme: HNMT - 5.3 uM Histamine; GNMT - >500 uM Glycine; PNMT - 16.2 uM Norephinephrine; COMT - 13.7 uM Norephinephrine; NNMT - 3.8 uM Nicotinamide; GAMT - 2.5 uM Guanidinoacetate.6, 8, 10. Room temperature
6. Final reaction conditions: 10 nM COMT, 5 uM SAM, 15 uM norepinephrine, 50 mM Tris, pH 8.0, 3 mM MgCl2, 1 mM EDTA, 50 mM NaCl, 1 mM DTT, and 0.1 mg/mL BSA; refer to tables 2 and S1 for specific timing.
8. Conversion of SAH to ADP; MTase Glo Kit (Promega, Madison, WI).
10. Conversion of ADP to ATP and detection by UltraGlo luciferase; MTase Glo Kit (Promega, Madison, WI).
11. Settings: 20 s exposure, 1X binning, high gain, medium speed.

REFERENCES:
Inglese J, Shamu CE and Guy RK, Reporting data from high throughput screening of small molecule libraries, Nature Chemical Biology, 2007, 3(8): 438-441. doi.org/10.1038/nchembio0807-438.

Comment: Disclaimer:
Although all reasonable efforts have been made to ensure the accuracy and reliability of the data, caution should be exercised when interpreting the results as artifacts are possible from nonspecific effects such as assay signal interference. The curve fitting and activity calls presented here are based on the NCATS analysis methods.

Compound Ranking:
1. Compounds are assayed at single point activity (40 uM).
2. Active / Inactive compound calling is based on the results of the enzyme assay panel. ACTIVE compounds have PUBCHEM_ACTIVITY_SCORE = 50 and are compounds that have <= -50% max response in ANY ONE of the six enzymes. INACTIVE compounds have PUBCHEM_ACTIVITY_SCORE = 0 and are those that have >= -30% max response in ALL SIX enzymes. The remaining compounds are INCONCLUSIVE and have PUBCHEM_ACITIVITY_SCORE = 30.

External ID: MScreen:TargetID_600

Protocol: C-terminally 6xHis tagged CDK2/Cyclin A complex and N-terminally Flag tagged CDC25B C473S (372-566) were expressed and purified. Proteins were incubated together at a final concentration of 125 nM each for 1 hr prior to incubation with compound for 1 hr, followed by addition of anti-6xHis europium cryptate donor beads (Cisbio) and anti-Flag XL-665 acceptor beads (Cisbio) at a final dilution of 1:350 for 1 hr. 20mM potassium fluoride was added 10 minute prior to plate reading. Assay reagents were dispensed using a multidrop liquid dispenser (Thermo Scientific) onto uncoated, black, low-volume, 384-well plates (Corning). Assay plates were quantified using an Envision plate reader (Perkin-Elmer) with excitation of the europium crytate donor at 337 nm wavelength and emission of the donor at 620 nm and emission of the XL-665 acceptor at 665 nm in 18 uL volumes. Assays were performed in a buffer containing 50 mM Tris (pH 7.5), 50 mM NaCl, 10mM MgCl2, 1mM TCEP, with addition of and 1mM ATP, 0.05% BSA, and 0.05% Tween-20 immediately prior to the start of the assay.

Comment: The activity outcome is based on a Z-score (number of standard deviations from the negative control mean) of 3 or higher on at least 50% times that the sample was screened.
For instance, if the sample was screened in n=4 runs, it would be considered active only if it had a Z-score of 3 or above in at least 2 runs.

This screen was funded by NIH grant number: R01CA181185

External ID: HMS1303

Protocol: Prior to screening, lyophilized FITC-GIV peptide (a.a. 1671-1701) is dissolved in 100% DMSO to a concentration of 0.5 mM, then further diluted with water to a final concentration of 50 microM. One stock was prepared in batch for the entire screen and aliquoted. All protein stocks were stored at -80C. Thawing of aliquots on the day of the assay was performed rapidly at room temperature.

Prior to transfer of screening compounds, experimental wells of 384-well assay plates were pre-filled with 37.8 nM of FITC-GIV peptide (for 25 nM final concentration) in a 10 microL volume of assay buffer (50 mM Tris [pH 7.4], 100 mM NaCl, 10 mM MgCl2, 5 mM EDTA, 0.4% NP-40, 30 microM GDP, 1 mM DTT). Control wells were pre-filled with 37.8 nM of FITC-GIV peptide in 10 microL of assay buffer containing either 1% DMSO (vehicle negative control) or 45.3 microM AlCl3+15.1 mM NaF (AlF4- positive control). Each plate contained 16 negative control and 16 positive control wells. Plates were centrifuged at 1000xg for 2 minutes to eliminate bubbling on the surface. Following, 100 nL of experimental compound was pin-transferred into individual wells for each of two replicate assay plates (A&B). After pin-transfer, 5 microL of 3 microM His-tagged rat Galphai3 purified from E. coli (for 1 microM final concentration) was added to each well, and assay plates were shaken at low speed for 5 seconds. Final assay volume was 15 microL. Plates were centrifuged at 1000xg for 2 minutes to eliminate bubbling on the surface and shaken for 10 seconds prior to an incubation of 90 minutes at room temperature. Plates were protected from prolonged light exposure. All manipulations were performed at room temperature.

Assay plates were read with a PerkinElmer Wallac EnVision Multilabel 2103 plate reader using the fluorescent polarization measurement technology with a D505fp/D535 dual mirror and a 480 nm excitation filter. 535 nm emission filters were used for P and S channel reads at 11 mm measurement height with 30 flashes and detector gains of 319 and 563. G-factor 0.96.

Negative control: DMSO
Positive control: Aluminum tetrafluoride (AlF4-, composite of NaF and AlCl3)

Comment: Calculated result values and scoring of active compounds:

Z-score: Indicates the number of standard deviations an experimental condition is from the mean. It is calculated based on plate average (u) and standard deviation (s) of experimental well fluorescence polarization (FP) measurements for each replicate. Z-score (z) is defined as the quotient of the mean of the experimental well population subtracted from an individual well's FP (x), divided by the standard deviation within the experimental wells; z = (x-u)/s.

Normalized percent control: calculated by subtracting plate average positive control FP from experimental well FP, dividing by the difference between plate average negative and positive control FP, and multiplying by 100.

STD: the number of standard deviations from the plate average negative control FP for each replicate experimental well

Compound wells with FP values exceeding +5 standard deviations from the negative control sample average were flagged as potential aggregators or fluorescence quenchers due to their high polarization signal (HighPol) and were excluded from further consideration. Activity scores were calculated by averaging the replicate normalized percent of control values and subtracting from 100 (score based on single replicate if data for other replicate was excluded for any reason). Result values < 0 were set to 0 (no activity) and > 100 were set to 100 (100% activity). Compounds with activity score >= 15 were considered active.

External ID: VANDERBILT_HTS_GIRK2_MPD

Protocol: To screen for modulators of the G protein-gated inwardly-rectifying potassium channel subunit 2 (GIRK2) homomeric channels, HEK293 cells were engineered to overexpress GIRK2. These cells were screened using a high-throughput thallium-flux assay in a 384-well format. High-throughput thallium flux assays are based on three principles: (1) extracellular thallium can permeate through potassium channels into cells, (2) the fluorescent dye Thallos enters and stays in the cytoplasm of HEK293 cells, and (3) the fluorescence of Thallos increases dramatically when it interacts with thallium ions. Compounds that modulate the activity of an overexpressed channel, in this case GIRK2, are identified by the change in fluorescence that results from changes in thallium influx into cells through the overexpressed channel.

The screening protocol was conducted as follows. One hour prior to screening, cells were loaded with 1.5 micromolar (muM) Thallos in assay buffer (1x Hank's Balanced Salt Solution and 20 millimolar (mM) HEPES). The liquid handling and imaging was conducted using a kinetic-imaging plate reader, Panoptic (WaveFront Biosciences). Before screening, Thallos-containing buffer was removed from cells and replaced with 20 microliters (muL) per well of assay buffer. Compounds were dissolved in assay buffer at 20 muM. After 8 seconds of imaging, 20 muL of compound solution was added per well and allowed to incubate for 150 seconds. Next, 10 muL of a solution containing 2.0 mM thallium in Base Buffer (125 mM NaHCO3, 1 mM MgSO4, 1.8 mM CaSO4, 5mM Glucose, and 20 mM HEPES) was added to the wells. 30 seconds later, 12 muL of base buffer containing 2.0 mM thallium and 50 mM 2-methyl-2,4-pentanediol (MPD), a partially-activating concentration, was added to each well. MPD has is a previously-described GIRK2 channel activator. Data was collected for 60 seconds after this final addition. The positive control for this screen was 30 muM ivermectin, a natural product previously identified as a GIRK2 activator as part of a small-scale pilot screen. Microsoft Excel was utilized for data analysis. Data were normalized, F/Fo, on a well-to-well basis to account for differences in cell number. Compound activity was analyzed by comparing the sums of control-subtracted amplitudes of fluorescence intensity at 20 seconds after each thallium addition. The top 0.2% compounds corresponding to wells that demonstrated the largest increases in fluorescence were selected as "hits" for counter screening, as described below.

All 63,228 compounds screened using the method described above are listed in column OUTCOME_SCREEN_HITS. The 133 compounds selected as hits based on the above criteria are labelled with "100" in the ACTIVITY column. Fluorescent compounds were included in the inactive compounds and marked with "0" in the ACTIVITY column.

The 133 active compounds from column OUTCOME_SCREEN_HITS were tested for non-specific activity in untransfected HEK293 cells using assay conditions otherwise identical to the primary screen. Column OUTCOME_HEK_COUNTERSCREEN lists the 23 compounds that displayed an increase in fluorescence upon thallium addition with "100" in the ACTIVITY column.

The 110 compounds which were identified as hits in the primary screen but inactive when tested in untransfected HEK293 cells were tested for activity in GIRK2-overexpressing HEK293 cells that did not express NPY4 receptor. Column OUTCOME_GIRK2_COUNTERSCREEN lists the 44 compound that displayed an increase in fluorescence upon thallium addition with "100" in the ACTIVITY column.

The 44 active compounds from column OUTCOME_GIRK2_COUNTERSCREEN were tested at various concentrations to determine if compound activity was concentration dependent. Column OUTCOME_GIRK2_DOSE_RESPONSE provides the efficacy of these compounds; activity of all compounds at the provided concentrations was normalized to the activity of VU0537695 at 25 muM, which was the highest efficacy observed during this screening. For each compound concentration listed, the efficacy of that compound provided refers to the normalized, control-subtracted fluorescence intensity at 15 seconds after the addition of thallium. The 28 compounds that demonstrated >5% efficacy and concentration-dependent activity were labelled as "100" in the ACTIVITY column.

Finally, column PUBCHEM_ACTIVITY_OUTCOME combines all of the information from the above counterscreens together, indicating the 28 hits from this GIRK2 screen.

Comment: