User:Bjl012

General Summary How are Ion Pumps and Agrin Signaling Integrated? NKA also known as sodium, potassium, and ATPase is known to have contributed in many ion transport roles throughout the body in the plasma membrane. But the ironic fact is that the idea of transport chains that involves these ions is mostly related to that of the brain as fifty percent of the brains energy is used to transports ions across the plasma membrane. In this paper I will be discussing about Agrin a large proteoglycan that is located in the brain leading to the activation of signaling cascades and the inhibition of the NKA. The first main component to start this cascade is that the use of ATP hydrolysis generates the active transport of the potassium and sodium ions across the plasma membrane which allows the body to carry its everyday functions such as essential for the electrical excitability and the secondary uptake and extrusion of ions, nutrients, and neurotransmitters, and the regulation of the pH throughout the body and the regulation of the cells volume. Agrin is composed of many domains in which it contains an alpha and a beta cleavage site. The alpha cleavage site is located on the SEA domain of Agrin which is approximately around the middle of the chain and the beta cleavage site is located in between the EG and G3 domain of the Agrin chain which is approximately located on the right end of the chain. The Neurotrypsin that is located inside that of the presynaptic cells cleaves Agrin in that of two homologous spots the Alpha site (located on the SEA domain) and the beta site (is located in between the EG and G3). The cleavage allows for the formation of different concentrations of the Agrin that can change the pumping into that of signaling. The C22 and C15 of the Agrin is formed. In the first step the C22 of Agrin displaces the Beta subunit of the NKA which causes the ions not to flow through the channel due to inhibition. The C15 of Agrin comes in and knocks off the C22 of Agrin leading to the prevention of inhibition of the channels because the C15 fragment does not contain the inhibitory site that means that it does not inhibit the NKA function. In overall it is very difficult to understand the functions of Agrin and its contribution to the signaling and that of pumping of ions. At first the two homologous sites are cleaved on the Agrin chain leading to the release of Agrin C22, which inhibits the pumping of the ions in the plasma membrane. Which can lead to many consequences such as the depolarization of the membrane and increased action potentials of the of the cortical neurons. That is why Agrin C15 comes into play to stop the inhibition and to let the ions pass freely through the plasma membrane. Agrin is very important to be studied for scientists as it leads to the studies of mental retardation and if it relates to the lack of neurotrypsin in that of humans. This in possibility will help us fully realize the full potential of Agrin as it relates to mental retardation and hopefully a cure that we can find.