BIOLOGY 2B03 Lecture Notes - Lecture 6: Gtpase, Stat5, Stat Protein
Document Summary
Tyrosine kinase-linked receptors = cytokine receptor of jak/stat pathway that control production of red blood cells. Receptor tyrosine kinase (rtk) that is linked to phosphorylation cascade through a small. G-protein coupled receptors that activate an effector protein inside the cell to produce a secondary messenger, camp, that regulates cell metabolism. Red blood cells (erythrocytes) are replaced when mitotically-proliferating stem cells (or progenitor cells) stop dividing and instead differentiate. The signal of maturation is the cytokine, erythropoietin (epo) Expression of epo is regulated by an oxygen-binding transcription factor in kidney cells. Epo is released into the circulatory system, however it is only the erythrocyte progenitor cells that carry an epo receptor (epor) Epor is a cytokine receptor linked to the jak-stat signal transduction pathway. Inactive epor is a monomeric single pass transmembrane protein, however the epo signal interacts with two epor, initiating dimerization. Cellular responses include inhibition of cell death, changes in patterns of gene expression and differentiation.