Signal Sequences & Transport

What determines whether an ERSS-containing protein will be secreted when the transport vesicle fuses with the cell membrane or whether the ERSS-containing protein will become part of the cell membrane?

• the presence or absence of an ERSS

• the presence or absence of a stop transfer sequence

• the presence or absence of an NLS or NES

SNAREs function in which step of

the life of a vesicle?

• Budding

• Docking

• Fusion

• Transport

Which of these is NOT a step in nuclear transport?

• NLS gets recognized by importin

• Ran-GEF exchanges Ran GDP to Ran GTP

• The NLS gets cleaved

• Ran-GAP hydrolysis Ran GTP

A signal sequence on the polypeptide chain targets all but which proteins to the rough ER surface?

• Golgi proteins

• plasma membrane proteins

• lysosomal

• mitochondrial

Adaptor proteins ____________ & coat proteins ______________

• direct budding ; select cargo

• select cargo ; direct budding

• transport the protein ; recognize the target

• recognize the target ; transport the protein

Which of the following is responsible for specifically targeting proteins to the Golgi membrane?

• ERSS

• a stop transfer sequence of the correct length

• none of these options

• MP6

Release of the ERSS from the SRP upon arrival to the translocon does not require energy.

• true

• false

Secreted proteins and celular membrane proteins share these characteristics, EXCEPT for

• both follow the secretory pathway

• both have an ERSS

• both have a stop transfer sequence

Proteins moved from point C to point D are transported by vesicles that are coated with

• COP I

• COP II

• clathrin

A protein that is found in the membrane domain at point D must have the following signal sequences: (select all that apply)

• ERSS

• NLS

• NES

• MP6

• stop transfer sequence