Glycogen synthase expression of the muscle isozyme and not the liver isozyme. However, muscle-specific glycogen synthase activation may lead to excessive accumulation of glycogen, leading to damage in the heart and central nervous system following ischemic insults. The reaction is highly regulated by allosteric effectors such as glucose-6-phosphate (activator) and by phosphorylation reactions (deactivating). Glucose-6-phosphate allosteric activating action allows glycogen synthase to operate as a glucose-6-phosphate sensor. The inactivating phosphorylation is triggered by the hormone glucagon, which is secreted by the pancreas in response to decreased blood glucose levels. The enzyme also cleaves the ester bond between the C1 position of glucose
Organ transplantation in fiction Organ transplantation in fiction Organ transplantation is a common theme in science fiction and horror fiction. Numerous horror movies feature the theme of transplanted body parts that are evil or give supernatural powers, with examples including "Body Parts", "Hands of a Stranger", and "The Eye". Organ transplants from donors who are unwilling, or incapable of objecting, to having their organs removed are a recurring theme in dystopian fiction. In contrast to unwilling organ donors, there is the theme of individuals who want to donate their own life-critical organs, such as a brain or heart, at the cost of their own