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: HMS791

Protocol: Prior to screening, FITC LANA1-23 was stored lyophilized at -80 degC and freshly purified chicken nucleosomes were stored at 4 degC in 20 mM Tris pH 7.5, 600 mM NaCl, 0.2 mM EDTA, 0.5 mM B-Mercaptoethanol.

On the day of screening, FITC LANA1-23 was resuspended at 50 uM in TEN-BT buffer (10 mM Tris-HCl (pH 7.5), 1 mM EDTA (pH 8.0), 2.5 mM NaCl, 5 mM Beta-mercaptoethanol, 0.01% Triton-X-100) and diluted to a final concentration of 50 nM in TEN-BT buffer plus 240 nM of purified nucleosomes (480 nM LANA peptide binding sites). 30 uL per well were dispensed in column 1-22 in Corning #3575 black 384 well plates.

Wells in column 23 contained 30 uL of the same mixture (for pilot screen) or with the addition of 10 uM monensin (for HTS) as a negative control. In column 24, 1250 nM unlabeled WT LANA1-23 peptide (for pilot screen) or 10 uM mitoxantrone (for HTS) was added to the wells as a positive control. Compounds were transferred into wells via stainless steel pin array (100 nL) and the reaction was incubated at room temperature for 10 to 45 minutes (stable for up to 2 hours). Library plates were screened in duplicate, with both assay plates in a given set prepared on the same day.

Following a room temperature incubation of 10 to 45 minutes, the assay is read on a EnVision plate reader using a 480 nM excitation filter, 535 nM S and P emission filters and D505fp/D535 dichoric mirror. mP value for FP measurement = 1000*(S-G*P)/(S+G*P) where S= , P=, G= G-factor. The G Factor = 1.

Comment: LANA 1-23 peptide containing the first 23 amino acids of the LANA protein from Kaposi's sarcoma herpesvirus (KSHV) was synthesized with an N-terminal FITC via a beta alanine linker and HPLC purified (peptide sequence: [FITC]-Beta alanine-MAPPGMRLRSGRSTGAPLTRGSC-[NH2]).

Data analysis: Z-scores were calculated for each replicate well using the mean and standard deviation of plate experimental well FP values. Compounds were considered active if the Z-score for both replicates < -2. Wells with high total fluorescence intensity (high S and P channel values) were excluded from further consideration. Activity scores were calculated based on replicate average FP Z-scores. For wells with average Z-score >= 0, the activity score was set to 0. For wells with replicate average Z-score < 0, replicate Z-score was divided by 4 and multiplied by -100. The replicate average was then used to determine the well activity score. Values > 100 (replicate average Z-score < -4) were set to 100.