RI1 是一种选择性RAD51的抑制剂，IC50值为 5-30 μM，可以破坏人类细胞中的同源重组。它在半胱氨酸 319 处与 RAD51 蛋白表面共价结合，并通过直接结合到 RAD51 细丝中蛋白质亚基之间的界面的蛋白质表面来灭活 RAD51。

RI-1 is a RAD51 inhibitor (IC50: 5-30 μM).

在HeLa细胞,MCF-7和U2OS三种癌细胞株中,RI-1具有单剂毒性（LD50：20-40 μM）。 通过直接和特异破坏HsRAD51和抑制RAD51,RI-1可抑制RAD51在ssDNA上形成丝的能力,从而使细胞对DNA损伤的敏感性增加。RI-1使G2期细胞的γ-H2AX灶减少,并使辐射6小时后未修复DSB的水平增加。

DNA binding assays: All reactions are performed in black non-binding polystyrene 384-well plates with reaction volumes of 30–100 μL. Purified DNA strand exchange proteins and chemical compounds are pre-incubated at room temperature for 5 minutes; they are then further incubated at 37°C for 30 min with 100 nM of ssDNA substrate, consisting of a 45-mer poly-dT tagged with Alexa 488 at the 5' terminus (synthesized and purified by Integrated DNA Technologies). Reactions are performed in 20 mM HEPES pH 7.5, 10 mM MgCl2, 0.25 μM BSA, 2% glycerol, 30 mM NaCl, 4% DMSO and 2 mM ATP. Some conditions included DTT or TCEP (tris(2-carboxyethyl)phosphine) as indicated. DNA binding is measured as a function of fluorescence polarization (FP) with a Safire2 plate reader, using the following settings: excitation 470±5 nM, emission 530±5 nM, 10 reads/well, Z height and G factor auto-calibrated from control wells. Displayed error bars represent standard deviation. For experiments involving a titration of protein concentrations, data are fit to an equation that accounts for the cooperative nature by which recombinase proteins bind DNA. For experiments involving a titration of RI-1, protein concentrations are selected to give an ～80% saturation of the FP signal in the absence of RI-1.

Cytotoxicity is determined by loss of colony-forming ability. Experiments are performed in triplicate. Crystal violet stained colonies are imaged with a CCD camera and counted using NIH Image software. Error bars denote standard error.(Only for Reference)

415713-60-9

C14H11Cl3N2O3

361.6

RI1;RAD51 inhibitor 1;RI-1; 3-氯-1-(3,4-二氯苯基)-4-(4-吗啉基)-1H-吡咯-2,5-二酮

DMSO:36.2 mg/mL (100 mM)
Powder: -20°C for 3 years
In solvent: -80°C for 2 years