• Open Access

Importins and exportins in cellular differentiation


  • Guest Editor: L. M. Popescu

Correspondence to: Mamoru ISEMURA,
Graduate School of Nutritional and Environmental Sciences,
University of Shizuoka, 52–1, Yada, Shizuoka 422-8526, Japan.
Tel.: +81–54–264—5824
Fax: +81-54-264-5824
E-mail: isemura@u-shizuoka-ken.ac.jp


  • • Introduction
  • • Importins and exportins
  • • NLS and NES
  • • Cargo molecules
  • • Importins and exportins In cellular differentiation
    • - HL-60 cell differentiation
      • - Importin expression
      • - Exportèn expression
      • - Monocyte differentiation
      • - Terminal erythroìd differentiation
      • - Neural differentiation
      • - Cardiac differentiation
      • - Keratìnocyte differentiation
      • - Germ cell maturation
      • - Muscle cell differentiation
  • • Concluding remarks


The importin/exportin transport system provides the machinery involved in nucleocytoplasmic transport. Alterations of the levels of importins and exportins may play crucial roles in development, differentiation and transformation. Employing human leukaemia HL-60 cells, we and others have revealed the differentiation-associated changes in the protein and gene expression of these factors. The recent finding that a switch to the importin-α subtype triggers neural differentiation of embryonic stem cells underscores the importance of nucleocytoplasmic transport factors in cellular events. This review focuses on current research into the roles of importins and exportins in cell differentiation.