CH. 12: Wrap Up Assignment COMPLETE Flashcards
In the cell biology field’s current hypothesis regarding evolution of eukaryotes, the nuclear membrane is derived from ___________ an ancient archaeon.
invagination of the plasma membrane of
engulfment of a photosynthetic bacterium by
engulfment of an aerobic bacterium by
all of the above
invagination of the plasma membrane of
If Ran GAPs are mutated such they are non-functional,
Ran will remain active until its native GTPase activity hydrolyzes GTP
Ran will be more rapidly inactivated
both of the above
Ran will remain active until its native GTPase activity hydrolyzes GTP
In the cell biology field’s current hypothesis regarding evolution of eukaryotes, mitochondria are derived from ___________ an ancient eukaryotic (or perhaps archaeal) cell.
engulfment of an aerobic bacterium by
engulfment of a photosynthetic bacterium by
invagination of the plasma membrane of
all of the above
engulfment of an aerobic bacterium by
The nuclear localization signal of a transcription factor called BIOL3040. Normally, BIOL3040 would be localized in ___________, and when the central lysine of the NLS patch is monoubiquitinated, the protein would be in __________.
the cytosol; the nucleus
the cytosol; the cytosol
the nucleus; the cytosol
the nucleus; the nucleus
the nucleus; the cytosol
An experimenter manipulates gene expression in a eukaryotic cell, such that its lamins cannot be dephosphorylated. What would be a consequence?
nuclear division could not occur
the nuclear lamina could not reassemble after mitosis
nuclear pores could not disassemble
the nuclear lamina could not disassemble before nuclear division
the nuclear lamina could not reassemble after mitosis
If Ran GEFs are mutated such they are no longer functional,
Ran will more rapidly bind GTP
When Ran attains its GDP-bound state, it will remain in that form
Ran will be rapidly activated
When Ran attains its GDP-bound state, it will remain in that form
Misfolded proteins in the ER lumen can be:
translocated to the cytosol through a translocator protein
moved by vesicular transport to the Golgi
moved by vesicular transport to the proteasome
trafficked in vesicles to the cytosol
all of the above
translocated to the cytosol through a translocator protein
The sequence of nuclearly-encoded protein of the thylakoid space is mutated so that it does not contain a thylakoid signal sequence. Where this protein be localized when its trafficking is complete?
matrix
inner membrane
intermembrane space
cytosol
stroma
stroma
Which motif would be most likely to target proteins to the mitochondria?
an SKL motif
KDEL motif
ER signal sequence
mannose 6-phosphate
an amphipathic helix with abundant postively-charged amino acid side chains lined up along one side
an amphipathic helix with abundant postively-charged amino acid side chains lined up along one side
A mitochondrial inner membrane protein that is encoded by the mitochondrial genome must be translocated through:
a translocator of the outer membrane
a translocator of the inner membrane
neither of the above
neither of the above
The machinery for insertion of beta-barrel pore proteins into the outer bacterial membrane is similar to:
the sorting and assembly machinery of the mitochondrial outer membrane
protein translocators of the outer membrane
both
the sorting and assembly machinery of the mitochondrial outer membrane
Mitochondrial proteins that are encoded by the nuclear genome are synthesized:
on ribosomes at the rough ER
on free, cytosolic ribosomes
on ribosomes in the mitochondrial matrix
both B and C
on free, cytosolic ribosomes
Which would be a response that would decrease the number of new unfolded proteins?
a general decrease in translation
selective increase in expression of proteins involved in protein folding in the ER (e.g. chaperones)
both of the above
both of the above
A resident protein of the ER lumen, Protein X, is mutated such that it cannot properly fold. A cell that expresses this mutant Protein X is treated with a chemical that prevents function of the proteasome. Under these conditions.
Protein X is trafficked by vesicles to the proteasome
polyubiquitinated Protein X accumulates in the cytosol
Protein X moves from the ER to the Golgi and then to lysosomes for degradation
Protein X accumulates in the ER lumen
polyubiquitinated Protein X accumulates in the cytosol
Where would the C-terminal of this membrane protein be? The red and orange stretches are transmembrane helices. First, look at the first transmembrane domain, and determine which side of the ER membrane the N terminal will be on. Then, follow the protein as it crosses the membrane, crosses back, crosses again, and crosses back again…
non-cytosolic side
ctyosolic side
could be either
not enough information to determine
non-cytosolic side
