Cells Alive 4: Vesicular transport Flashcards
What are the functions of the endoplasmic reticulum?
Protein biosynthesis
* Lipid biosynthesis
* Intracellular Ca2+ store
What happens at the RER?
Folding of proteins
What happens at the SER?
Synthesis of lipids
What are some post-translational modifications in the ER?
Adding disulphide bonds to help stabilise the protein,
What is Haemagglutinin an example of?
A chaperone protein
Where does carbohydrate synthesis occur?
Golgi apparatus
What is the fate of receptors?
can be recycled at the early endosome
What is the fate of early endosomes?
Recycled into late endosomes
What is the function of the lysosome?
To degrade products, and also to protect enzymes from being degraded
What is the function of (COP I, COP II or clathrin)
Curved coat proteins, help form vesicles and tell the vesicle where to go
What is cargo release mediated by?
Changes in pH
What is the constitutive secretory pathway?
Proteins do not require a signal to be secreted through this pathway
What is the regulated secretory pathway?
Requires specialised secretory cells and uses hormones, neurotransmitters etc.
What is the structure of the endoplasmic reticulum?
It is made up of tubules and sacs surrounded by membranes
Where are the ER tubules and sacs developed from?
the nuclear outer membrane, they are connected between each other and protrude into the cytoplasm
What is the name of the space enclosed by the sacs?
lumen or ER cisternal space
What does N-glycosylation do?
Attaches multiple branched sugars to the amide nitrogen of an Asn, this helps stabilise, protect from degradation and serves as a signal for interaction with other proteins
Where are completed proteins sent after modifications?
Golgi apparatus
What are some modifications that may occur at the golgi apparatus>
post-translational modification of proteins and lipids, O-linked glycosylation, sulphation
how do snares work?
Each vesicle has a v-snare which is complimentary to a target t-snare, they wrap around eachother forming a trans-SNARE complex
What is the trans-SNARE complex?
where membranes are locked together, this mediates membrane fusion
