Release triggered

Binding to Gpy locks the flexible switch regions I and II of Ga into a conformation that firmly binds GDP but is nonproductive for GTP binding and hydrolysis. The replacement of GDP with GTP causes local but dramatic conformational changes to switch regions I and 11, as shown in the Go GTP-yS structure, which disrupt nearly all of the contacts between Gp. and Ga in the switch interface, thereby triggering release of Ga from Gpy (see Figures 13.10 and 13.11). 

Fig. 4.9 Temperature and pH-value (qualitatively) in the different cycles of an automatic dishwashing program and the dissolution of a tablet with temperature triggered release of rinse aid.

Blaustein Earlier, Rick Paul raised the issue of the release sites. One thing we have seen in cultured cells is that there are frequent release sites. We also saw this when we were looking at sparks. There are some special areas within the cells. The SR is not uniform in this sense. The question is where those release sites are. There is another issue concerning Ca2+-induced Ca2+ release. If there is freely diffusible Ca2+ within the SR, Ca2+ is released into the cytosol and this triggers release next door. Then if there is diffusion away from the next door site simply because Ca2+ has been vacated from the place it is released from, there is a problem. As one part of the SR is emptied of Ca2+, if Ca2+ is freely diffusible it will not be there at the next sites that haven t released yet. This is something that hasn t been addressed. There are some real problems in terms of having a freely communicating intraluminal SR. 

RyRs do not exist as isolated SR ion channels, but as protein complexes subject to modulation by cellular metabolites, [Ca2+] , kinases and other factors (e.g. Marx et al 2000). Currently, very little is known with respect to the expression and localization of RyR isoforms, the regulatory factors underlying sensitivity of the complex to gating, and the effect of luminal (SR) Ca2+ on the probability of spontaneous or triggered release. A renewed focus on the role of RyRs in smooth muscle should help move the field from the initial discovery of these exciting phenomena to a clearer understanding of the function of this system in diverse smooth muscle tissues. 

Hirst That would be nice. It is possible that there is Ca2+ entry triggering release from an InsP3 store not linked to ryanodine. As far as I can gather that is unlikely to happen. 

Event 9 Fire/Explosion—Sulfur dioxide and sulfuric acid. Motiva Enterprises, LLC, Delaware City, Delaware (July 17, 2001). Collapse of a spent sulfuric acid storage tank (more than 250,000 gallons) triggered releases from nearby tanks, killed one contract worker, and caused a large fish kill. Other commonly bermed tanks were immersed in concentrated sulfuric acid for several days until they could be drained, but they did not fail ("News Link" Environmental 2008). 

Antonsson and Marinou 2000 Adams and Cory, 1998). Stress may also cause inaease, nitric oxide (NO), or reactive oxygen species (ROS) production which, in turn, triggers release of apoptotic proteins from the intermemhrane space (Kroemer and Reed, 2000 Vieira et at, 2000). Release of these proteins from mitochondria are required for stress induced killing hut are, with a few exceptions (Bergmann et al, 1994, Schulze- Osthoff et al, 1993), dispensible for CD95 and TNF-receptor transduced apoptosis. These other death processes require FADD and caspase-8 to be recruited into the death receptor complexes and cannot be blocked by Bcl-2 (Krammer, 2000 Scaffidi et al, 1998). 

Shin J, Shum P, Thompson D. Acid-triggered release via dePEGylation of DOPE liposomes containing acid-labile vinyl ether PEG-lipids. J Contr Rel 2003 91 187. 

Ishida T, et al. Targeted delivery and triggered release of liposomal doxorubicin enhances cytotoxicity against human B l5miphoma cells. Biochim Biophys Acta 2001 1515 144. 

Psychostimulants Trigger release, block reuptake of NE tf Dopamine ADHD Augmentation for depression ( )... 

Layer-by-layer electrostatic deposition of biopolymers at interface of emulsion droplets Polyelectrolyte capsules microparticles with novel functionality and triggered release multiple layers around oil droplets exhibiting improved stability towards environmental stresses (temperature, ionic strength, pH, freezing, dehydration) McClements, 2005, 2006 Sanguansri and Augustin, 2006... 

Phospholipase C hydrolyzes the bond between glycerol and phosphate in phosphatidylinositol 4,5-bisphos-phate, releasing two products inositol 1,4,5-trisphos-phate (IP3), which is water-soluble, and diacylglycerol, which remains associated with the plasma membrane. IP3 triggers release of Ca2+ from the endoplasmic reticulum, and the combination of diacylglycerol and elevated cytosolic Ca2+ activates the enzyme protein kinase C. 

At the distal tip of the axon are voltage-gated Ca2+ channels. When the wave of depolarization reaches these channels, they open, and Ca2+ enters from the extracellular space. The rise in cytoplasmic [Ca2+] then triggers release of acetylcholine by exocy-tosis into the synaptic cleft (step (3) in Fig. 12-5). Acetylcholine diffuses to the postsynaptic cell (another... 

Schematic diagram of a synaptic junction in which acetylcholine is the chemical transmitter. Arrival of an action potential at the terminus of the presynaptic cell (top) stimulates Ca2+ uptake, which triggers release of acetylcholine (ACh) from vesicles near the terminus of the...

The single action revolver requires the firer to cock the hammer by hand between shots. A pull on the trigger releases the hammer which is rotated forward by its compressed spring... 

Calcineurin. The calcineurin, or Ca2+-calmodulin dependent protein phosphatase (Aramburu et al., 2004) mediates apoptosis through at least two routes. First, this action can be achieved through steroid receptor Nur77 and CD95 ligand this pathway was found in lymphoid cells (Shi et al., 1989). Alternatively, calcineurin dephosphorylates a pro-apoptotic protein Bad (a member of Bcl-2 family), which in turn translocates into mitochondria and triggers release of cytochrome C and activation of caspases (Wang et al., 1999). 

---