China
Africa
Explore chapters and articles related to this topic
Cellular and Immunobiology
Published in Karl H. Pang, Nadir I. Osman, James W.F. Catto, Christopher R. Chapple, Basic Urological Sciences, 2021
Masood Moghul, Sarah McClelland, Prabhakar Rajan
Golgi apparatus receives proteins from the ER and packages them for exocytosis.Stored in vesicles until signals are received, triggering their transport to the cell membrane.Fusion of vesicle to the cell membrane triggered by SNARE proteins.Exocytosis may be calcium-dependent (regulated) (e.g., nerve cells) or -independent (unregulated).Exocytosis also expels messages outside the cell to communicate with the environment.
Interactions with Medical-Aesthetic Treatments
Published in Paloma Tejero, Hernán Pinto, Aesthetic Treatments for the Oncology Patient, 2020
Silvia Gabriela Ortiz Zamorano, Victoria Zamorano Triviño
Botulinum toxin achieves a neuromuscular block by translocating its light chain, released into the intracellular medium that acts by highly specific zinc-dependent endopeptidases with proteolytic activity, which divide one or more of the SNARE proteins of each neurotoxin, inhibiting the coupling and fusion between vesicles and receptors, and thereby blocking the release of exocytotic neurotransmitters [12]. In any situation where neuromuscular transmission is compromised, therefore, the injection of botulinum toxin could theoretically increase the underlying clinical picture [13].
Homeostasis of Dopamine
Published in Nira Ben-Jonathan, Dopamine, 2020
The SNARE proteins are broadly divided into two categories: vesicular or v-SNAREs, which are incorporated into the membranes of the vesicles during budding, and target or t-SNAREs, which are associated with membranes of the nerve terminal. The SNAREs are small, abundant proteins which are often posttranslationally inserted into membranes via a C-terminal transmembrane domain. Seven of the 38 known SNAREs, including SNAP-25, do not have a transmembrane domain and are attached to the membrane through lipid modifications such as palmitoylation.
The complementary roles of VAMP-2, -3, and -7 in platelet secretion and function
Published in Platelets, 2023
Smita Joshi, Kanakanagavalli Shravani Prakhya, Alexis N. Smith, Harry Chanzu, Ming Zhang, Sidney W. Whiteheart
Platelet extracts from V3−/−7−/− and V2∆3∆7−/− mice were prepared and probed by immunoblotting to confirm the losses of the VAMPs and to determine if other SNARE proteins were altered in these strains. There were no significant differences in the levels of the t-SNAREs, SNAP23, and syntaxin 11 nor were two α granule proteins, Platelet Factor 4 (PF4) and P-selectin, affected (Figure 1). Levels of granule marker cargos, e.g., serotonin-uptake for dense granules, PF4 for α granules, and β-hexosaminidase for lysosomes, were not altered in platelets from any of the strains when compared to wild-type (Figure S2). Most notably, V8 was unchanged in both strains. As expected, fibrinogen levels were reduced in both V3−/−7−/− and V2∆3∆7−/− platelets. This is consistent with our earlier report that V3 plays a role in endocytosis.9
A novel RRGW derived peptide is a promising inhibitor of BoNT/A
Published in Journal of Enzyme Inhibition and Medicinal Chemistry, 2023
Wantong Ma, Lulu Wang, Xiangmin Tan, Xin Wang, Chunyan Yang, Yu Wang, Ziye Liu, Bo Liu, Hai Zhu, Dejuan Zhi, Dongsheng Wang
Botulinum neurotoxins (BoNTs) produced by the bacteria Clostridium botulinum, are the most toxic biotoxins that can cause flaccid paralysis leading to death1. According to their immunological characteristics, there are seven serotypes of botulinum neurotoxins, designated from BoNT/A to BoNT/G2. The toxins can bind to the specific neuronal receptors in the neuromuscular junctions (NMJs), where they cleave the soluble N-ethylmaleimide-sensitive factor attachment receptor (SNARE) proteins to block acetylcholine release and consequently cause flaccid paralysis3. BoNTs are generally composed of a heavy chain (HC, 100 KDa) and a light chain (LC, 50 KDa) covalently linked by a disulphide bond. The HC is responsible for binding to the receptor on the surface of the neuronal cells, and then assisting the LC to translocate into the cytosol, where the SNARE proteins serve as the relative substrates of the LCs. The synaptosome-associated 25 KDa protein (SNAP-25) can be cleaved by BoNT/A and E4, VAMP2 can be cleaved by BoNT/B, D and G, and both SNAP-25 and syntaxin can be cleaved by BoNT/C.
Modulating insulin secretion and inflammation against sodium arsenite toxicity by levosimendan as a novel pancreatic islets’ protector
Published in Toxin Reviews, 2023
Marzieh Daniali, Mona Navaei-Nigjeh, Maryam Baeeri, Soheyl Mirzababaei, Mahdi Gholami, Mahban Rahimifard, Mohammad Abdollahi
Regarding the insulin secretion pathway, it should be noted that insulin is produced in the endoplasmic reticulum and stored and transported in vesicles. Insulin is released from β-cells by exocytosis involving the attachment of secretory vesicles to the plasma membrane by a group of proteins called SNARE. The interaction of these proteins with the plasma membrane forms a stable complex that prepares the membrane for attachment and fusion to the granule. The exocytosis of vesicles is also regulated by Ca2+ concentration. Some studies also showed that as insulin granules become acidic, structural changes occur in the SNARE protein, facilitating its attachment to the membrane. By acting on the insulin gene transcription promoter, NaAsO2 toxin causes the cell to lose sensitivity to extracellular glucose concentrations and alter the stability of insulin mRNA, which is typically affected by glucose concentrations (Meloni et al.2013).