Identification of Nuclear Import and Export Signals Within the Structure of the Zinc Finger Protein TIS11

Biochem Biophys Res Commun. 2002 May 17;293(4):1242-7. doi: 10.1016/S0006-291X(02)00363-7.

Abstract

TIS11, a member of the CCCH zinc finger protein family, functions as a positive transcriptional regulator. TIS11 was localized in both the cytoplasm and nucleus when transiently expressed in COS-7 cells. Upon treatment with leptomycin B, a specific inhibitor of the nuclear export receptor CRM1, a marked nuclear accumulation of TIS11 was observed, indicating that TIS11 shuttles between the nucleus and the cytoplasm. By deletion studies using a green fluorescent protein fusion system, we have mapped a functional nuclear localization signal (NLS) to a region containing two tandem repeats of the zinc finger motif of TIS11. A site-directed mutagenesis analysis of TIS11 NLS has revealed the critical importance of two arginine residues (Arg127 and Arg131 in the rat TIS11). Furthermore, we demonstrated that the N-terminal Leu-rich region of TIS11 serves as an LMB-sensitive nuclear export signal (NES), indicating that TIS11 follows a CRM1-mediated export pathway. These results suggest that TIS11 is subject to constant nucleocytoplasmic shuttling due to its NLS and NES.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Active Transport, Cell Nucleus
  • Amino Acid Motifs
  • Amino Acid Sequence
  • Animals
  • Antibiotics, Antineoplastic / pharmacology
  • Arginine / chemistry
  • Base Sequence
  • COS Cells
  • Cell Nucleus / metabolism*
  • Cytoplasm / metabolism
  • DNA, Complementary / metabolism
  • DNA-Binding Proteins*
  • Fatty Acids, Unsaturated / pharmacology
  • Gene Deletion
  • Green Fluorescent Proteins
  • Immediate-Early Proteins / chemistry*
  • Immediate-Early Proteins / metabolism*
  • Karyopherins / metabolism
  • Luminescent Proteins / metabolism
  • Microscopy, Fluorescence
  • Models, Genetic
  • Molecular Sequence Data
  • Plasmids / metabolism
  • Protein Binding
  • Protein Conformation
  • Rats
  • Receptors, Cytoplasmic and Nuclear*
  • Recombinant Fusion Proteins / metabolism
  • Sequence Homology, Amino Acid
  • Signal Transduction
  • Time Factors
  • Transfection
  • Tristetraprolin
  • Zinc Fingers

Substances

  • Antibiotics, Antineoplastic
  • DNA, Complementary
  • DNA-Binding Proteins
  • Fatty Acids, Unsaturated
  • Immediate-Early Proteins
  • Karyopherins
  • Luminescent Proteins
  • Receptors, Cytoplasmic and Nuclear
  • Recombinant Fusion Proteins
  • Tristetraprolin
  • Zfp36 protein, rat
  • exportin 1 protein
  • Green Fluorescent Proteins
  • Arginine
  • leptomycin B