Signal Hypothesis:
Prediction that proteins bounds for the endomembrane system have a "zip code" analogous to the nuclear localization signal. The idea is that first amino acids act as a signal that brings the protein into the lumen of the ER, called the ER Signa
l Sequence (20 amino acids).Endomembrane System:
The main function of the Endomembrane system is to produce protein through the use of the nucleus for the "data," the rough ER for the production, and the Golgi Apparatus to be "finished." The proteins help the cell and other cells. Endomembrane System also makes lipids going through the smooth ER instead of the rough ER. This is important because lipids make up membranes and are the number one ingredient in cells.
Nuclear Envelope:
Material can get in and out of the nucleus through a protein trnasporter, the nuclear pore complex. Molecules can get through the nuclear pore complex by having a "zip code" chemical, nuclear localization signal. The protein is integrated in the nuclear envelope which give protection of the DNA and chromosomes.
Rough ER:
- Structure:
- Single Membrane, integrated proteins
- Ribosomes
- Lumen, interior of the sac-like structure
- Function:
- Protects the production of proteins and supports the structure of rough ER
- Ribosomes are embedded on the outside of the organelle and are key in the production of the protein.
- Lumen is where the protein is folded and other types of processing
- Structure:
- Single membrane, integrated proteins
- enzymes
- sac like branches
- Function:
- Protection of lipid synthesize
- Catalyze reactions to produce lipids and phospholipids
- Help keep interior structure for the smooth ER
Golgi Apparatus:
- Strucutre:
- Single membrance, receptors of products of the rough ER
- Flattened cisternae, stacked on top of another
- Function:
- Protects the finishing products of protein and pinch off into vesicles that deliver the products