The role of VAMP7/TI-VAMP in cell polarity and lysosomal exocytosis in vivo.

Traffic

Department of Cellular and Molecular Biology, Laboratory for Molecular Traffic, Institute for Molecular and Cellular Regulation, Gunma University, Maebashi 371-8512, Japan.

Published: October 2011

VAMP7 or tetanus neurotoxin-insensitive vesicle- associated membrane protein (TI-VAMP) has been proposed to regulate apical transport in polarized epithelial cells, axonal transport in neurons and lysosomal exocytosis. To investigate the function of VAMP7 in vivo, we generated VAMP7 knockout mice. Here, we show that VAMP7 knockout mice are indistinguishable from control mice and display a similar localization of apical proteins in the kidney and small intestine and a similar localization of axonal proteins in the nervous system. Neurite outgrowth of cultured mutant hippocampal neurons was reduced in mutant neurons. However, lysosomal exocytosis was not affected in mutant fibroblasts. Our results show that VAMP7 is required in neurons to extend axons to the full extent. However, VAMP7 does not seem to be required for epithelial cell polarity and lysosomal exocytosis.

Download full-text PDF

Source
http://dx.doi.org/10.1111/j.1600-0854.2011.01247.xDOI Listing

Publication Analysis

Top Keywords

lysosomal exocytosis
16
cell polarity
8
polarity lysosomal
8
neurons lysosomal
8
vamp7 knockout
8
knockout mice
8
vamp7 required
8
vamp7
6
role vamp7/ti-vamp
4
vamp7/ti-vamp cell
4

Similar Publications

MYO18B promotes lysosomal exocytosis by facilitating focal adhesion maturation.

J Cell Biol

March 2025

Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, China.

Many cancer cells exhibit increased amounts of paucimannose glycans, which are truncated N-glycan structures rarely found in mammals. Paucimannosidic proteins are proposedly generated within lysosomes and exposed on the cell surface through a yet uncertain mechanism. In this study, we revealed that paucimannosidic proteins are produced by lysosomal glycosidases and secreted via lysosomal exocytosis.

View Article and Find Full Text PDF

A hyaluronic acid nanogels based exosome production factory for tumor photothermal therapy and angiogenesis inhibition.

Int J Biol Macromol

December 2024

School of Chemical Engineering and Technology, Tianjin University, Tianjin 300350, PR China. Electronic address:

Exosomes as a unique drug delivery system provide a new choice for tumor therapy. However, the in vitro functionalization of exosomes and the process of circulating drug delivery can easily cause exosome degradation and drug loss, thus reducing the efficiency of drug delivery. In this work, based on the endocyto-fusion-exocytosis pathway of exosome formation, a multifunctional hyaluronic acid nanogel loaded with the antiangiogenic drug vatalanib and the near-infrared photothermal agent indocyanine green (ICG) was designed.

View Article and Find Full Text PDF

The cRGD peptide surface coating strategy for photothermal therapy nanoplatforms shows great promise in developing safe and effective cancer therapies. However, the precise intracellular mechanisms of these platforms remain unclear due to the complexity of intracellular trafficking and nano-bio interactions. This study investigates the nano-bio interactions of BiSe nanofoams, a representative photothermal therapy nanoplatform, coated with cRGD peptide in cancer cells, focusing on endocytosis, exocytosis, and cellular trafficking.

View Article and Find Full Text PDF

TRPML1 agonist ML-SA5 mitigates uranium-induced nephrotoxicity via promoting lysosomal exocytosis.

Biomed Pharmacother

December 2024

Institute of Radiation Medicine, Shanghai Medical College, Fudan University, No. 2094, Xie-Tu Road, Shanghai 200032, PR China. Electronic address:

Uranium (U) released from U mining and spent nuclear fuel reprocessing in the nuclear industry, nuclear accidents and military activities as a primary environmental pollutant (e.g., drinking water pollution) is a threat to human health.

View Article and Find Full Text PDF

Microglia degrade Alzheimer's amyloid-beta deposits extracellularly via digestive exophagy.

Cell Rep

December 2024

Department of Biochemistry, Weill Cornell Medicine, New York, NY 10065, USA. Electronic address:

Article Synopsis
  • Microglia develop acidic compartments, known as lysosomal synapses, to digest large amyloid-beta plaques through a process called digestive exophagy, utilizing exocytosed lysosomal enzymes.
  • Electron microscopy in 5xFAD mouse brains reveals that a lysosomal enzyme is secreted toward plaques, confirming this digestion mechanism.
  • The formation of these synapses is regulated by the PI3K-AKT pathway, and microglia can also exocytose small Aβ fibrils to target larger aggregates, potentially influencing the spread of amyloid-beta in Alzheimer's disease.
View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!