Disease relevance of KAP123

• The core protein of hepatitis C virus is imported into the nucleus by transport receptor Kap123p but inhibits Kap121p-dependent nuclear import of yeast AP1-like transcription factor in yeast cells [1].

High impact information on KAP123

• We show that the related protein Pse1p is also a karyopherin and can functionally substitute for Kap123p; both are capable of specifically directing a ribosomal nuclear localization signal reporter to the nucleus in vivo [2].
• Here, we identify a major distinct nuclear import pathway, mediated by a previously uncharacterized yeast beta karyopherin Kap123p [2].
• We report the identification of Yrb4p, a novel Gsp1p binding protein [3].
• Like importin-beta, Yrb4p and Pse1p specifically bind to Gsp1p-GTP, protecting it from GTP hydrolysis and nucleotide exchange [3].
• Thus, a major role of Pse1p, Kap123p, and Sxm1p may be nuclear export rather than import, suggesting a symmetrical relationship between these processes [4].

Biological context of KAP123

• Intersection of the Kap123p-mediated nuclear import and ribosome export pathways [5].
• To further explore the role of Kap123p in nucleocytoplasmic transport and ribosome biogenesis, we performed a synthetic fitness screen designed to identify genes that interact with KAP123 [5].

Other interactions of KAP123

• Pse1p is predominantly necessary for nuclear uptake of H3 and H4, while Kap104p and Yrb4p also support import [6].

References