Adaptor Proteins, Signal Transducing/metabolism* ; Humans

BACKGROUND: Arteriosclerosis obliterans (ASO) is a major cause of adult limb loss worldwide. Autophagy of vascular endothelial cell (VEC) contributes to the ASO progression. However, the molecular mechanism that controls VEC autophagy remains unclear. In this study, we aimed to explore the role of the GRB2 associated binding protein 1 (GAB1) in regulating VEC autophagy. METHODS: In vivo and in vitro studies were applied to determine the loss of adapt protein GAB1 in association with ASO progression. Histological GAB1 expression was measured in sclerotic vascular intima and normal vascular intima. Gain- and loss-of-function of GAB1 were applied in VEC to determine the effect and potential downstream signaling of GAB1. RESULTS: The autophagy repressor p62 was significantly downregulated in ASO intima as compared to that in healthy donor (0.80 vs. 0.20, t = 6.43, P < 0.05). The expression level of GAB1 mRNA (1.00 vs. 0.24, t = 7.41, P < 0.05) and protein (0.72 vs. 0.21, t = 5.97, P < 0.05) was significantly decreased in ASO group as compared with the control group. Loss of GAB1 led to a remarkable decrease in LC3II (1.19 vs. 0.68, t = 5.99, P < 0.05), whereas overexpression of GAB1 significantly led to a decrease in LC3II level (0.41 vs. 0.93, t = 7.12, P < 0.05). Phosphorylation levels of JNK and p38 were significantly associated with gain- and loss-of-function of GAB1 protein. CONCLUSION Loss of GAB1 promotes VEC autophagy which is associated with ASO. GAB1 and its downstream signaling might be potential therapeutic targets for ASO treatment.
Adaptor Proteins, Signal Transducing ; Adult ; Arteriosclerosis Obliterans/genetics* ; Autophagy ; GRB2 Adaptor Protein ; Humans ; Phosphoproteins/metabolism* ; Phosphorylation ; Protein Binding ; Signal Transduction

Death domain-associated protein (DAXX) as a multifunctional nuclear protein widely resides in nucleolus, nucleoplasm, chromatin, promyelocytic leukaemia nuclear bodies (PML-NBs) and cytoplasm. It plays significant roles in transcriptional regulation, apoptosis, cell cycle and other biological activities. Small ubiquitin-like modifier (SUMO) is required for SUMOylation which is a highly conserved post-translational modification in a wide variety of cellular processes. Numerous studies demonstrated that SUMOylation has a great effect on the subcellular localization and functional regulation of DAXX. This review will provide a summary for SUMOylation of DAXX.
Adaptor Proteins, Signal Transducing ; physiology ; Gene Expression Regulation ; Humans ; Nuclear Proteins ; physiology ; Sumoylation

OBJECTIVE: To observe the effects of Casitas B lymphoma (CBL) protein on proliferation, migration and invasion of breast cancer cells and explore its mechanism of action. METHODS: Cultured breast cancer cell lines MDA-MB-231 and MCF7A were transfected with a CBL-overexpressing plasmid and a specific siRNA targeting CBL (siRNA-CBL), respectively, and the changes in cell proliferation, migration and invasion were examined using colony-forming assay, cell counting kit-8 (CCK-8), scratch test and Transwell assay. Flow cytometry and Western blotting were performed to examine the effects of CBL overexpression on cell cycle and epithelial-mesenchymal transition (EMT) of MDA-MB-231 cells, and the changes in the number of filamentous pseudopodia were observed by rhodamine- labeled phalloidin staining of the cytoskeleton. IP-mass spectrometry identified NCK2 as the interacting proteins of CBL, and their interaction was verified by immunoprecipitation and immunofluorescence co-localization experiments in HEK-293T cells transfected with the plasmids for overexpression of CBL, NCK2, or both. Cycloheximide tracking and ubiquitination assays were used for assessing the effects of CBL on stability and ubiquitination of NCK2 protein in MDA-MB-231 cells; CCK-8 and Transwell assays were used to determine the effect of NCK2 overexpression on CBL-mediated proliferation and migration of the cells. RESULTS: The proliferation, migration and invasion were significantly suppressed in MDA-MB-231 cells overexpressing CBL (P < 0.05) and significantly enhanced in MCF7 cells with CBL silencing (P < 0.01). Silencing of CBL promoted G1/S transition in MCF7 cells (P < 0.05). Overexpression of CBL significantly decreased the expressions of CDK2/4 (P < 0.01), cyclinA2/B1/D1/D3/E2 (P < 0.05), Snail, N-cadherin, claudin-1 (P < 0.05), and upregulated the expression of E-cadherin (P < 0.05). CBL silencing upregulated the expressions of CDK2/4/6 (P < 0.05), cyclin A2/B1/D1/D3/E2 (P < 0.05), Snail, vimentin, and claudin-1 (P < 0.05) and down-regulated E-cadherin expression (P < 0.05). CBL overexpression obviously reduced the number of filamentous pseudopodia in MDA-MB-231 cells, and the reverse changes were observed in MCF7 cells with CBL silencing. In MDA-MB-231 cells, CBL overexpression lowered NCK2 protein stability (P < 0.05) and promoted its ubiquitin-mediated degradation (P < 0.01). Overexpression of NCK2 obviously reversed CBL-mediated inhibition of cell proliferation and migration (P < 0.01). CONCLUSION CBL can inhibit the proliferation, migration and invasion of breast cancer cells through ubiquitination-mediated degradation of NCK2.
Humans ; Sincalide ; Lymphoma ; Cytoskeleton ; Cadherins ; MCF-7 Cells ; Oncogene Proteins ; Adaptor Proteins, Signal Transducing

Dysregulation of the Wnt pathway has been extensively studied in multiple diseases, including some angiogenic disorders. Wnt signaling activation is a major stimulator in pathological angiogenesis and thus, Wnt antagonists are believed to have therapeutic potential for neovascular disorders. Actually, some Wnt antagonists have been identified directly from the anti-angiogenic factor family. This review summarizes the recent progress toward understanding of the roles of Wnt pathway antagonists in angiogenic regulation and their mechanism of action, and exploring their therapeutic potential.
Adaptor Proteins, Signal Transducing ; metabolism ; Animals ; Humans ; Neovascularization, Pathologic ; physiopathology ; Repressor Proteins ; metabolism ; Signal Transduction ; physiology ; Wnt Proteins ; antagonists & inhibitors

After 50 years of development in science of burns care in China, we have basically solved coverage of deep wounds of burn trauma, as well as role of multiple growth factors and stem cell in wound healing, making great contribution to improving the treatment of patients with large area of deep burns. Surgeons are paying close attention to problems of wound healing, especially in the fields of scarless healing and rehabilitation. To solve these problems, we need to do further investigation on multiple growth factors as well as proliferation/differentiation of stem cells in regulation of cell growth and differentiation in wound healing. Therefore, we are facing a even more serious challenge.
Adaptor Proteins, Vesicular Transport ; metabolism ; Burns ; metabolism ; Humans ; Signal Transduction ; Wound Healing

OBJECTIVETo analyze the structure and function of PYGO1 protein with bioinformatics.

METHODSThe bioinformatic methods and tools were used to analyze the physical and chemical properties, transmembrane region, hydrophobicity and hyrdrophilicity, secondary structure and functional category of PYGO1 protein.

RESULTSThe bioinformatic analysis revealed that proline content was the highest of all amino acid residues in PYGO1 protein; the molecular formula was C(1943)H(2937)N(577)O(635)S(18) with a relative molecular mass of 45; and the theoretical isoelectric point was 6.38. The analysis also demonstrated that PYGO1 was a hydrophilic and non-transmembrane protein; its main component was alpha-helix and random coil; it contained a plant homeodomain.

CONCLUSIONHuman pygo1 gene may act as a transcription regulation factor to regulate the heart development and the progress of heart diseases.

Intersectin is an evolutionarily conserved multifunctional adaptor protein with multifunctional domains. These domains interact with components of the endocytic and exocytic pathways, such as the clathrin mediating synaptic vesicle recycling, the protein related to endocytosis via caveolae, the with-no-lysine kinases related to the regulation of renal outer medullar potassium, and the Cdc42 mediating exocytic pathway. Recently, the understanding of intersectin function in the pathogenesis of endocrine tumor and many neurodegenerative diseases such as Down syndrome, Alzheimer disease has been deepened. This article reviewed the structure and roles in endocytosis/exocytosis and diseases of intersectin.
Adaptor Proteins, Vesicular Transport ; physiology ; Endocytosis ; Exocytosis ; Humans ; Synaptic Vesicles ; physiology

Epidermal growth factor receptor pathway substrate 8 (Eps8) is one of crucial kinase substrates for the epidermal growth factor receptors. Eps8 is related to mitosis and differentiation of normal cells. In recent years, it has been demonstrated that Eps8 involves in proliferation, metastasis and prognosis of many malignant tumors. Experiments have shown that Eps8 involves in Ras-Rac pathway of EGFR signaling by forming Eps8-Abi1-Sos1 tri-complex or participates in endocytosis mediated by rab5. Furthermore, Eps8 has also been found to regulate cell cycle. In conclusion, it may become a monitor and a new target for the treatment of malignant tumors. This review briefly introduces molecular structure and physiological function of Eps8, focusing on its function and molecular mechanism in proliferation, metastasis and prognosis of malignant tumors.
Adaptor Proteins, Signal Transducing ; metabolism ; Humans ; Neoplasm Metastasis ; Neoplasms ; metabolism ; pathology ; Prognosis

The aim of this study was to observe the inhibitory effect of daunorubicin on KG1a cells and the expression of Eps8 which is a novel tumor-associated antigen with its full name epidermal growth factor receptor pathway substrate 8 (Eps8), and to explore the effect of daunorubicin on Eps8 expression in KG1a cells at mRNA and protein levels. The KG1a cells were treated with different concentration of daunorubicin for 24, 48, 72 h, then trypan blue staining was used to detect the inhibitory rate of KGla cells, RQ-PCR and Western blot were used to detect Eps8 mRNA and Eps8 protein expression. The results showed that daunorubicin inhibited the proliferation of KG1a cells in a dose and time dependent manner (r = 0.983, P < 0.01). Daunorubicin could reduce the mRNA and protein levels of Eps8 expression in dose and time dependent manners in KG1a cells (r = 0.979, P < 0.05). It is concluded that with the increasing of concentration and time of daunorubicin acting on KG1a cells, the cell proliferative inhibitory effect increased and the expression of Eps8 decreased, suggesting that the inhibitory effect of daunorubicin on KG1a cell proliferation is realized through downregulation of Eps8 expression.
Adaptor Proteins, Signal Transducing ; metabolism ; Cell Line, Tumor ; Cell Proliferation ; drug effects ; Daunorubicin ; pharmacology ; Humans