Question

List what transport protein you think is MOST important in the body. Defend your answer (provide your rationale). Obviously there are a LOT of choices.

Answer 1

Sodium-potassium pump/sodium-potassium ATPase: A specialized transport protein found on the cell membrane. In 1950 it was discovered by the Jens Christian Skou. Initially, it binds to the ATP and three intracellular sodium cations. Hydrolysis of ATP causes the phosphorylation of aspartate amino acid of the sodium-potassium pump which induces the conformational change in the pump and transfers them to outside of the cell. The phosphorylated pumps are less affinity towards sodium cations but high affinity for extracellular potassium cations. Once the release of sodium cations outside of cell it binds to potassium cations which cause the dephosphorylation of the pump. Dephosphorylated pumps show a high affinity towards sodium cations and retain its original conformation again bind to the intracellular sodium cations.

Generation of nerve possible due to the presence of sodium-potassium pump on the cell membrane. The sodium-potassium pump creates the sodium and potassium chemical gradient of across the membrane. This chemical gradient used to maintain the resting membrane potential and to transmit the electrical signals along the neuronal cells. In kidney sodium-potassium pump involved in balancing of the sodium & potassium ions in the body. It also controls the cardiac muscle contraction and the blood pressure. It is involved in the secondary active transport of glucose and amino acids and maintains cell osmolarity of cells. In the brain, the cerebellar Purkinje neurons activity controlled by the sodium-potassium pump.