Indicate whether each of the following descriptions better applies to COPI- (1), COPII- (2), or clathrin- (3) coated vesicles. Your answer would be a four-digit number composed of digits 1 to 3 only, e.g. 1322.
( ) They are uncoated by an hsp70 family protein, which is stimulated by the binding of auxilin.
( ) They keep their coat proteins for a relatively long time, until they dock onto their target membrane.
( ) Their uncoating depends on activation of an ARF-GAP.
( ) Their uncoating depends in part on activation of a Sar1-GAP.

Question

Indicate whether each of the following descriptions better applies to COPI- (1), COPII- (2), or clathrin- (3) coated vesicles. Your answer would be a four-digit number composed of digits 1 to 3 only, e.g. 1322.
( )	They are uncoated by an hsp70 family protein, which is stimulated by the binding of auxilin.
( )	They keep their coat proteins for a relatively long time, until they dock onto their target membrane.
( )	Their uncoating depends on activation of an ARF-GAP.
( )	Their uncoating depends in part on activation of a Sar1-GAP.

Quizplus · Accepted Answer

Uncoating of COPII-coated vesicles may occur upon docking at a target membrane well after Sar1 hydrolyzes its bound GTP and is released. Clathrin- and COPI-coated vesicles, in contrast, shed their coat soon after they pinch off, through the activation of an uncoating ATPases or an ARF-GAP, respectively.

Indicate Whether Each of the Following Descriptions Better Applies to COPI-