Send to

Choose Destination
Biochem Biophys Res Commun. 2002 May 17;293(4):1242-7.

Identification of nuclear import and export signals within the structure of the zinc finger protein TIS11.

Author information

Department of Analytical Neurobiology, Faculty of Pharmacy, Meijo University, Tempaku, Nagoya 468-8503, Japan.


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.

[Indexed for MEDLINE]

Supplemental Content

Full text links

Icon for Elsevier Science
Loading ...
Support Center