BIOL 2021 Chapter 12.4: transporiing proteins into intermembrane space

• School: York University
• Department: Biology
• Course: BIOL 2021
• Professor: Patricia Lakin- Thomas

Document Summary

Same process to get into the inner membrane space. Protease cleaves off the stop transfer sequence and the protein is released in the intermembrane space. The reticulum forms a network of tubules and sacs. Lumen is a continuous space all tubules connect to each other and connect to the outer nuclear membrane. Smooth er: no ribosomes: lipid synthesis. The rough er and smooth er are continuous. Synthesis of lipids for organelles in the smooth er (ser) Calcium store high concentration of calcium in the lumen used for signaling: muscle cells have a sarcoplasmic reticulum which releases calcium to make muscles contract. Proteins start in the rough er, go to the matrix, go to vesicles and get transported to other organelles. In the rer, there is co-translational import: proteins are going in as they are being synthesized. Proteins translated in this method can be: water soluble proteins in the er lumen, transmembrane proteins embedded in the er membrane.