A fluorescence correlation spectroscopy-based assay for fragment screening of slowly inhibiting protein–peptide interaction inhibitors

详细信息    查看全文

• 作者：Junko Mikuni ; Miki Kato ; Shigenao Taruya ; Keiko Tsuganezawa ; Masumi Mori ; Naoko Ogawa ; Teruki Honma ; Shigeyuki Yokoyama ; Hirotatsu Kojima ; Takayoshi Okabe ; Tetsuo Nagano ; Akiko Tanaka
• 关键词：FCS ; Protein– ; protein interaction inhibitor ; FBDD ; Fragment screening
• 刊名：Analytical Biochemistry
• 出版年：2010
• 出版时间：1 July 2010
• 年：2010
• 卷：402
• 期：1
• 页码：26-31
• 全文大小：509 K

文摘

A fluorescence correlation spectroscopy (FCS)-based competitive binding assay to screen fragment-size compounds that weakly and slowly inhibit protein–peptide interactions was established. The interactions were detected by the increased diffusion time of a fluorescently labeled peptide probe after binding to its interacting protein. We analyzed the interactions between the c-Cbl TKB domain and phosphopeptides derived from ZAP-70, APS, and EGFR with the FCS assay and obtained 6 hit fragments that bound to the c-Cbl interaction sites. The binding amounts of the fragments were measured by direct binding measurements using surface plasmon resonance, and 5 fragments were found to bind selectively. The effect of 2 of the 5 fragments on the interaction with c-Cbl and the peptide exhibited strong time dependency. Furthermore, the inhibition by the selected 5 fragments on the protein–peptide interaction was confirmed by their effect on pull-down assays of c-Cbl with the biotin-conjugated interaction peptides. These results indicate the advantage of our FCS-based assay to study the time-dependent binding of compounds to their target protein.