Protein Transport
- Transcription occurs when changing DNA to mRNA, where the mRNA leaves the nucleus via pores in the nuclear envelope.
- Proteins are made on ribosome’s
- The ribosomes sometimes attach to the rER where the protein made moves through making the 3-D shape en route. (ribosomes on the rough endoplasmic reticulum make proteins that are excreted or attached to the cell membrane, whereas the ribosomes which are free in the cytoplasm make proteins which stay in the cytoplasm)
- Vesicles pinch off the rER, these contain the proteins.
- Then they are transported to the Golgi apparatus where the vesicle fuses with the flattened sacs of the Golgi apparatus; here the proteins may undergo further processing/moulding.
- Vesicles’ containing the modified protein pinches off the Golgi apparatus, to be transported around the cell. Such as extracellular enzymes will be moved to the cell membrane ready to be excreted.