Barnard D, Sun H, Baker L, Marshall M S
Department of Medicine, Indiana University School of Medicine, Indianapolis 46202, USA.
Biochem Biophys Res Commun. 1998 Jun 9;247(1):176-80. doi: 10.1006/bbrc.1998.8746.
Seven amino acid peptides were tested as in vitro inhibitors of oncogenic Ras-Raf association. The sequences of these peptides were derived from the H-Ras effector region (amino acids 25 to 51) and the Ras binding domain of Raf-1 (amino acids 64 to 105). Eleven out of the twenty-one Ras 7-mers tested inhibited formation of the Ras-Raf complex by at least 20% at 100 microM. The most potent of these inhibitory peptides contained the effector residues 32 to 37 or 40 to 45. Of the Raf-1 peptides tested, only the 94-ECCAVFR-100 and 95-CCAVFRL-101 peptides were significant inhibitors of Ras-Raf binding. The 95-101 Raf peptide had an IC50 value of 7 microM and also inhibited Ras-RalGDS binding. Analysis of the 95-101 peptide showed that its inhibitory activity required at least one cysteine followed by several hydrophobic residues. Our results demonstrate the feasibility of using small molecules as inhibitors of Ras protein-protein interactions.
对七种氨基酸肽进行了测试，以评估其作为致癌性Ras-Raf结合体外抑制剂的效果。这些肽的序列源自H-Ras效应区（第25至51位氨基酸）和Raf-1的Ras结合结构域（第64至105位氨基酸）。在测试的21种Ras七聚体中，有11种在100微摩尔浓度时能抑制Ras-Raf复合物的形成至少20%。这些抑制性肽中最有效的包含效应残基32至37或40至45。在测试的Raf-1肽中，只有94-ECCAVFR-100和95-CCAVFRL-101肽是Ras-Raf结合的显著抑制剂。95-101 Raf肽的IC50值为7微摩尔，并且还抑制Ras-RalGDS结合。对95-101肽的分析表明，其抑制活性至少需要一个半胱氨酸，随后是几个疏水残基。我们的结果证明了使用小分子作为Ras蛋白质-蛋白质相互作用抑制剂的可行性。
