BIOC 212 Lecture Notes - Lecture 3: Homeostasis, Macroglobulin, Isomerase
Document Summary
Interior is hydrophobic and this would expose lipids to the water not stable: membrane will spontaneously close/reseal due to hydrophobicity. In a cell, na+ would run in/k+ run out, dissipates the equilibrium. R, k, h, f, w, y, l, i degradation. Cellular membranes can only be made by expanding pre-existing membranes, not de novo. With very few exceptions, all proteins are encoded by nuclear genes and translated in the cytosol: only exceptions are encoded and translated in the mitochondria. Proteins must be sorted during or after translation to their correct compartment or membrane. Sorting information is carried inside the proteins themselves: protein sequence gives structure, function and localization. Image: from cytosol to er to golgi secretory system or endosomes: getting to the mitochondria is a different pathway. The sequence of a protein can encode a signal or signals that specify its organelle localization.