8/21 Cell Bioloy Flashcards
Describe how proteins are sorted to Nucleus
To move to the nucleus they travel through a nuclear pore. The pores allow small molecules up to about sixty kilodaltons. Anything larger than his most have a nucleus localizing signal. This signal is sufficient and necessary
Describe how proteins are sorted to mitochondra
The would be synthesized by the ribosome in the cytoplasm and then transported to the mitrochondria and accross the membrane of the mitochondria
Describe how proteins are sorted to lysosomes
they would be synthesized in the cytoplasm and then transported to, and accross the membrane of the lysosome
Describe how proteins are sorted to plasma membrane
The protiens have a signal sequence on the end that tells the ribosome to take them to a translocation complex in the ER. Then the protein is co-translationally inserted in to the ER. then a stop transfer sequence causes the protein to be inserted in to the ER membrane and the rest is translated out of the ER. Then the signal sequence is cleaved, the end inside the ER can be glycosilated etc. Vesicle pinch off, and go to golgi then bud off again to go to the membrane
Describe the function of the endoplasmic reticulum in sorting and transporting proteins to different compartments of the cell
The ER acceptes the transmembrane protiens and the extracellular protiens. It modifies the protiens by adding sugars and other chemistry, then it makes sure that the protien is folded correctly.
Describe the function of the Golgi apparatus in sorting and transporting proteins to different compartments of the cell
The golgi will sort and modify the protien and bud off vesicles to transport it to different locations or backwards. they physically sort them together and send them off to their destination
Describe the function of the lipid vesicles in sorting and transporting proteins to different compartments of the cell
They contain receptors that sort specific products and then proteins that coat and cause the vesicle to bud off and transport the protiens to the destinaiton. 3 outcomes for the vesicles from the golge: Regulated pat to the plasma membrane, default constituative pathway straight to the membrane and dump the material. and Sent with a specific signal someplace else
Predict how mutations in genes affect the sorting of proteins to target compartments.
genes that we talked about include: nuclear localization signals, signals to other organelles, snares to dock and release the vesicles. Signal sequence to the ER, Nuclear export signals etc.
what mutations in the CFTR gene lead to what clinical symptoms in cystic fibrosis patients.
The CFTR gene can be mutated in numerous ways and many different steps in the production of the CFTR protien at which to fail. The failed protien will tend to accumulate at the point of failure. (ER, Golgi, Vesicle etc.). leads to build up of mucus, chlorine sweat etc.
Identify the two components of “Basic Science” in Medicine as the large body of facts that must be accumulated and the process of generating and evaluating hypotheses (clinical reasoning).
Clinicians must be rational scientist as well! Accumulate possible hypothesis based on knowledge, and then evaluate the hypotheses.
How would we localize a cytoplasmic kinase to he nucleus?
By attaching a nuclear localizing signal to it. This is sufficient and necessary
What is a differential diagnosis
A full and inclusive list of the possible afflictions of the patient. This must be unbiased as possible and inclusive as necessary so as to include the actual disease or condition. This summary of the possibilities would then need to be sorted and tested in order to narrow the diagnosis towards the actual affliction.
what are the 3 ways to get somewhere for a protein?
Born/Stay there
Go through a pore
Cross a Membrane
the infor is in the protein to where it need to go!
How does a protien fold and what if it doesn’t
Use of chaperones, the protien will be tagged with a sugar that will be bound by a chaperone and then try to fold proper. Multiple rounds of this process:
Folding and modification of prteins in the ER are interdependent, active processess that regulate the rate of protein production and chaperone synthesis through the feedback system known as the unfolded protein response. (includes ubiquidation and degridation!)
What proteins cause the formation of vesicles
COP and Clatherin
