Identification and Functional Characterization of a Novel Nuclear Localization Signal Present in the Yeast Nab2 Poly(A)+ RNA Binding Protein

The nuclear import of proteins bearing a basic nuclear localization signal (NLS) is dependent on karyopherin alpha/importin alpha, which acts as the NLS receptor, and karyopherin beta1/importin beta, which binds karyopherin alpha and mediates the nuclear import of the resultant ternary complex. Recently, a second nuclear import pathway that allows the rapid reentry into the nucleus of proteins that participate in the nuclear export of mature …