3SB54 Interactions of adaptor proteins in the intracellular vesicle transport : receptors, ubiquitin, and small GTPases

We directly visualized the uptake and intracellular vesicle transport of shortened single walled carbon nanotubes in living cells through a dual-labeling system. With a stable labeling of fluorescein isothiocyanate and a pH-sensitive stacking of doxorubicin on carbon nanotubes, the location of internalized nanotubes inside the cell and the microenvironment especially the pH change of the nanotube-embedded vesicles could be monitored at the same time. Results showed that after internalization through endocytic pathway, carbon nanotubes tended to transport from the early endosomes to later acidic lysosomes and these vesicles moved along the microtubule track toward a perinuclear region where is a microtubule-organizing center. These results might provide a novel understanding for the intracellular interaction of carbon nanotubes and living cells.

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Exploring Proteomic Drug Targets, Therapeutic Strategies and Protein - Protein Interactions in Cancer: Mechanistic View

Current Cancer Drug Targets ◽

10.2174/1568009618666180803104631 ◽

2019 ◽

Vol 19 (6) ◽

pp. 430-448 ◽

Cited By ~ 1

Author(s):

Khalid Bashir Dar ◽

Aashiq Hussain Bhat ◽

Shajrul Amin ◽

Syed Anjum ◽

Bilal Ahmad Reshi ◽

...

Keyword(s):

Protein Interactions ◽

High Throughput Screening ◽

Critical Role ◽

Cancer Therapeutics ◽

Adaptor Proteins ◽

Therapeutic Strategies ◽

Small Gtpases ◽

Beta Catenin ◽

Protein Protein Interactions ◽

Apoptosis Protein

Protein-Protein Interactions (PPIs) drive major signalling cascades and play critical role in cell proliferation, apoptosis, angiogenesis and trafficking. Deregulated PPIs are implicated in multiple malignancies and represent the critical targets for treating cancer. Herein, we discuss the key protein-protein interacting domains implicated in cancer notably PDZ, SH2, SH3, LIM, PTB, SAM and PH. These domains are present in numerous enzymes/kinases, growth factors, transcription factors, adaptor proteins, receptors and scaffolding proteins and thus represent essential sites for targeting cancer. This review explores the candidature of various proteins involved in cellular trafficking (small GTPases, molecular motors, matrix-degrading enzymes, integrin), transcription (p53, cMyc), signalling (membrane receptor proteins), angiogenesis (VEGFs) and apoptosis (BCL-2family), which could possibly serve as targets for developing effective anti-cancer regimen. Interactions between Ras/Raf; X-linked inhibitor of apoptosis protein (XIAP)/second mitochondria-derived activator of caspases (Smac/DIABLO); Frizzled (FRZ)/Dishevelled (DVL) protein; beta-catenin/T Cell Factor (TCF) have also been studied as prospective anticancer targets. Efficacy of diverse molecules/ drugs targeting such PPIs although evaluated in various animal models/cell lines, there is an essential need for human-based clinical trials. Therapeutic strategies like the use of biologicals, high throughput screening (HTS) and fragment-based technology could play an imperative role in designing cancer therapeutics. Moreover, bioinformatic/computational strategies based on genome sequence, protein sequence/structure and domain data could serve as competent tools for predicting PPIs. Exploring hot spots in proteomic networks represents another approach for developing targetspecific therapeutics. Overall, this review lays emphasis on a productive amalgamation of proteomics, genomics, biochemistry, and molecular dynamics for successful treatment of cancer.

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Molecular cloning of the mouse homologue of Rab3c

Journal of Molecular Endocrinology ◽

10.1677/jme.0.0270117 ◽

2001 ◽

Vol 27 (1) ◽

pp. 117-122 ◽

Cited By ~ 3

Author(s):

NJ Pavlos ◽

J Xu ◽

JM Papadimitriou ◽

MH Zheng

Keyword(s):

Skeletal Development ◽

In Situ Hybridisation ◽

Matrix Vesicles ◽

Matrix Vesicle ◽

Predicted Amino Acid Sequence ◽

Multiple Sequence ◽

Intracellular Vesicle ◽

Intracellular Vesicle Transport ◽

The Brain

Small GTP-binding proteins of the Rab subfamily are key regulators of intracellular vesicle transport. Here we report the isolation of a cDNA clone encoding the complete Rab3c isoform from mouse embryo using a degenerative PCR-based approach. Multiple sequence alignment revealed that the predicted amino acid sequence was identical to the previously identified rat Rab3c isoform and 98% identical to the published bovine Rab3c GTPase from brain. Furthermore by in situ hybridisation, Rab3c mRNA was detectable within various regions of the brain, cartilage and highly enriched within intestinal villi of foetal tissues. Chondrocytes in the hypertrophic zone, but not reserve or proliferative zones, expressed high levels of Rab3c. This pattern of expression corresponds with the genesis of matrix vesicles during endochondral ossification.In all, our results suggest that in addition to its functional role during regulated secretion in brain, Rab3c may play a part in matrix vesicle trafficking during skeletal development.

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Fusion of sequentially internalized vesicles in alveolar macrophages.

The Journal of Cell Biology ◽

10.1083/jcb.110.4.1013 ◽

1990 ◽

Vol 110 (4) ◽

pp. 1013-1022 ◽

Cited By ~ 18

Author(s):

D M Ward ◽

D P Hackenyos ◽

J Kaplan

Keyword(s):

Endocytic Pathway ◽

Receptor Complexes ◽

Intracellular Vesicle ◽

Late Endosomes ◽

Early Endosomes ◽

Changing Patterns ◽

Intracellular Vesicle Transport ◽

Shift Technique ◽

Ligand Addition ◽

Density Shift

Previously we reported that internalized ligand-receptor complexes are transported within the alveolar macrophage at a rate that is independent of the ligand and/or receptor but is dependent on the endocytic apparatus (Ward, D. M., R. S. Ajioka, and J. Kaplan. 1989. J. Biol. Chem. 264:8164-8170). To probe the mechanism of intracellular vesicle transport, we examined the ability of vesicles internalized at different times to fuse. The mixing of ligands internalized at different times was studied using the 3,3'-diaminobenzidine/horseradish peroxidase density shift technique. The ability of internalized vesicles to fuse was dependent upon their location in the endocytic pathway. When ligands were administered as tandem pulses a significant amount of mixing (20-40%) of vesicular contents was observed. The pattern of mixing was independent of the ligands employed (transferrin, mannosylated BSA, or alpha macroglobulin), the order of ligand addition, and temperature (37 degrees C or 28 degrees C). Fusion was restricted to a brief period immediately after internalization. The amount of fusion in early endosomes did not increase when cells, given tandem pulses, were chased such that the ligands further traversed the early endocytic pathway. Little fusion, also, was seen when a chase was interposed between the two ligand pulses. The temporal segregation of vesicle contents seen in early endosomes was lost within late endosomes. Extensive mixing of vesicle contents was observed in the later portion of the endocytic pathway. This portion of the pathway is defined by the absence of internalized transferrin and is composed of ligands en route to lysosomes. Incubation of cells in iso-osmotic medium in which Na+ was replaced by K+ inhibited movement of internalized ligands to the lysosome, resulting in ligand accumulation within the late endocytic pathway. The accumulation of ligand was correlated with extensive mixing of sequentially internalized ligands. Although significant amounts of ligand degradation were observed, this compartment was devoid of conventional lysosomal markers such as acid glycosidases. These results indicate changing patterns of vesicle fusion within the endocytic pathway, with a complete loss of temporal ligand segregation in a prelysosomal compartment.

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