The Peptide-Mediated Interactions Between Human Osteoclast-Stimulating Factor and Its Partner Proteins in Osteoporosis: Which Binds to Which?
详细信息 查看全文
- 作者：Yaodong Zhou ; Jinlian Liu ; Qing Zhou…
- 关键词：Peptide ; mediated interaction ; SH3 domain ; Peptide ; Osteoclast ; stimulating factor ; Osteoporosis
- 刊名：International Journal of Peptide Research and Therapeutics
- 出版年：2017
- 出版时间：March 2017
- 年：2017
- 卷：23
- 期：1
- 页码：61-67
- 全文大小：
- 刊物类别：Biomedical and Life Sciences
- 刊物主题：Biochemistry, general; Animal Anatomy / Morphology / Histology; Polymer Sciences; Pharmaceutical Sciences/Technology; Pharmacology/Toxicology; Molecular Medicine;
- 出版者：Springer Netherlands
- ISSN：1573-3904
- 卷排序：23
文摘
Human osteoclast-stimulating factor (hOSF) is an intracellular protein produced by osteoclasts that induces osteoclast formation and bone resorption in osteoporosis by recruiting multiple signaling complexes with its diverse biological partners through peptide-mediated interactions (PMIs). The protein contains a modular peptide-recognition domain of Src homology 3 (SH3), which can recognize and bind to the polyproline regions of its partner proteins, as well as two N-terminal polyproline segments, which can be recognized and bound by the SH3 domains of its partner proteins. Here, we attempted to elucidate the complicated PMIs between the different SH3 domains and different polyprolines of hOSF and its three known interacting partners, i.e. proto-oncogene tyrosine-protein kinase (c-Src), survival motor neuron (SMN) and Src-associated in mitosis, 68 kD (Sam68). A total of 29 peptide segments containing the SH3-binding motif PXXP were extracted from these partner proteins, which are potential binding sites of hOSF SH3 domain, while the c-Src kinase also possesses a SH3 domain that may recognize and bind the two polyproline peptides at hOSF N-terminus. Structural bioinformatics analysis identified a number of biologically functional PMI candidates between these SH3 domains and these polyproline peptides, which were then tested in vitro using fluorescence spectroscopy assays. Consequently, it is found that (i) hOSF SH3 domain exhibits strong binding potency to two Sam68 peptides 36RQPPLPHR43 (Kd = 13.7 μM) and 425APPARPVK432 (Kd = 3.2 μM) as well as moderate affinity to three SMN peptides 193FLPPPPPM200 (Kd = 56.2 μM), 235PFPSGPPI242 (Kd = 28.4 μM) and 246PPPICPDS253 (Kd = 74.5 μM), but has only weak or no binding to c-Src peptides. Instead, a proline-rich region at hOSF N-terminal that contains two overlapping peptides (3KPPPKPVK10 and 6PKPVKPGQ13) can be bound tightly by c-Src SH3 domain with high and moderate affinity (Kd = 5.8 and 39.6 μM, respectively).