Format

Send to

Choose Destination
Biochem J. 2001 Jun 1;356(Pt 2):495-501.

Role for phosphatidylinositol in nuclear envelope formation.

Author information

1
Department of Biology, Amherst College, Amherst, MA 01002, USA. b.larijani@icrf.icnet.uk

Abstract

PtdIns is a minor membrane phospholipid that is important in signal transduction. Recently, derivatives of PtdIns phosphorylated at the 3-position of the inositol ring have been implicated in the regulation of constitutive membrane traffic and in membrane fusion events. Assembly of the nuclear envelope (NE), a crucial step in the progress of mitosis, is also likely to involve membrane fusion reactions. We therefore investigated the role of PtdIns and phosphoinositide 3-kinase (PI-3K) activity in NE formation in vitro. GTP-induced NE formation was blocked by wortmannin and LY294002, two specific inhibitors of PI-3K, suggesting a role for PtdIns phosphorylated at the 3-position. PtdIns-specific phospholipase C mimicked GTP hydrolysis as an inducer of NE formation. This induction was dependent on a membrane vesicle subfraction (MV1) that was highly enriched in PtdIns, as determined by heteronuclear two-dimensional NMR spectroscopy. On the basis of these results, we suggest that the MV1 population serves as a source of membranes rich in PtdIns that might facilitate fusion, possibly through the production of the membrane-destabilizing lipid diacylglycerol.

PMID:
11368777
PMCID:
PMC1221861
DOI:
10.1042/0264-6021:3560495
[Indexed for MEDLINE]
Free PMC Article

Supplemental Content

Full text links

Icon for HighWire Icon for PubMed Central
Loading ...
Support Center