Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2000 Mar 15;346 Pt 3(Pt 3):587-91.

Nuclear targeting of the beta isoform of type II phosphatidylinositol phosphate kinase (phosphatidylinositol 5-phosphate 4-kinase) by its alpha-helix 7

Affiliations

Nuclear targeting of the beta isoform of type II phosphatidylinositol phosphate kinase (phosphatidylinositol 5-phosphate 4-kinase) by its alpha-helix 7

A Ciruela et al. Biochem J. .

Abstract

Type II phosphatidylinositol phosphate kinases (PIPkins) have recently been found to be primarily phosphatidylinositol 5-phosphate 4-kinases, and their physiological role remains unclear. We have previously shown that a Type II PIPkin [isoform(s) unknown], is localized partly in the nucleus [Divecha, Rhee, Letcher and Irvine (1993) Biochem. J. 289, 617-620], and here we show, by transfection of HeLa cells with green-fluorescent-protein-tagged Type II PIPkins, that this is likely to be the Type IIbeta isoform. Type IIbeta PIPkin has no obvious nuclear localization sequence, and a detailed analysis of the localization of chimaeras and mutants of the alpha (cytosolic) and beta PIPkins shows that the nuclear localization requires the presence of a 17-amino-acid length of alpha-helix (alpha-helix 7) that is specific to the beta isoform, and that this helix must be present in its entirety, with a precise orientation. This resembles the nuclear targeting of the HIV protein Vpr, and Type IIbeta PIPkin is apparently therefore the first example of a eukaryotic protein that uses the same mechanism.

PubMed Disclaimer

References

    1. Nature. 1997 Apr 24;386(6627):779-87 - PubMed
    1. EMBO J. 1996 Dec 2;15(23):6516-24 - PubMed
    1. Biochem J. 1997 Oct 15;327 ( Pt 2):569-76 - PubMed
    1. Nature. 1997 Nov 13;390(6656):192-6 - PubMed
    1. Biochem J. 1998 Jan 1;329 ( Pt 1):115-9 - PubMed

Publication types

MeSH terms

Substances

LinkOut - more resources