The formation of a stable ternary complex involving Ran GTPase, a nuclear transport receptor, and a cargo protein occurs in ...
A) both nuclear import and export.
B) nuclear import , but not export.
C) nuclear export, but not import.
D) neither nuclear import nor export.

Question

Quizplus · Accepted Answer

In the nucleus, Ran-GTP binds to the importin in an importin-cargo complex, causing cargo release. This is in contrast to the binding of Ran-GTP to exportin, which promotes cargo binding and the formation of a ternary export complex. In the cytoplasm, Ran-GDP dissociates from the receptors, allowing importin to bind to its cargo and exportin to release its cargo.

The Formation of a Stable Ternary Complex Involving Ran GTPase