Nuclear translocation of phospholipase C-delta1 is linked to the cell cycle and nuclear phosphatidylinositol 4,5-bisphosphate.
Nuclear phosphoinositides, especially phosphatidylinositol 4,5-bisphosphate, fluctuate throughout the cell cycle and are linked to proliferation and differentiation. Here we report that phospholipase C-delta(1) accumulates in the nucleus at the G(1)/S boundary and in G(0) phases of the cell cycle. Furthermore, as wild-type protein accumulated in the nucleus, nuclear phosphatidylinositol 4,5-bisphosphate levels were elevated 3-5-fold, whereas total levels were decreased compared with asynchronous cultures. To test whether phosphatidylinositol 4,5-bisphosphate binding is important during this process, we introduced a R40D point mutation within the pleckstrin homology domain of phospholipase C-delta(1), which disables high affinity phosphatidylinositol 4,5-bisphosphate binding, and found that nuclear translocation was significantly reduced at G(1)/S and in G(0). These results demonstrate a cell cycle-dependent compartmentalization of phospholipase C-delta(1) and support the idea that relative levels of phosphoinositides modulate the portioning of phosphoinositide-binding proteins between the nucleus and other compartments.
Stallings
Jonathan D
JD
Department of Anesthesiology, State University of New York at Stony Brook, Stony Brook, NY 11794, USA.
Tall
Edward G
EG
Pentyala
Srinivas
S
Rebecchi
Mario J
MJ
D021581:Active Transport, Cell Nucleus; D000818:Animals; D015153:Blotting, Western; D002453:Cell Cycle; D002454:Cell Differentiation; D045744:Cell Line, Tumor; D002467:Cell Nucleus / Q000378:metabolism*; D049109:Cell Proliferation; D002855:Chromatography, Thin Layer; D003593:Cytoplasm / Q000378:metabolism; D018076:DNA, Complementary / Q000378:metabolism; D003902:Detergents / Q000494:pharmacology; D005347:Fibroblasts / Q000378:metabolism; D005434:Flow Cytometry; D019084:Fluorescent Antibody Technique, Indirect; D016193:G1 Phase; D005910:Glioma / Q000378:metabolism; D049452:Green Fluorescent Proteins / Q000378:metabolism; D006801:Humans; D007091:Image Processing, Computer-Assisted; D007527:Isoenzymes / Q000737:chemistry* / Q000378:metabolism*; D050356:Lipid Metabolism; D051379:Mice; D008856:Microscopy, Fluorescence; D008954:Models, Biological; D041681:NIH 3T3 Cells; D019269:Phosphatidylinositol 4,5-Diphosphate / Q000378:metabolism*; D054803:Phospholipase C delta; D017354:Point Mutation; D017434:Protein Structure, Tertiary; D021381:Protein Transport; D016192:Resting Phase, Cell Cycle; D016196:S Phase; D013347:Subcellular Fractions; D013997:Time Factors; D014162:Transfection; D010738:Type C Phospholipases / Q000737:chemistry* / Q000378:metabolism*
D018076:DNA, Complementary; D003902:Detergents; D007527:Isoenzymes; D019269:Phosphatidylinositol 4,5-Diphosphate; D049452:Green Fluorescent Proteins; D010738:Type C Phospholipases; C518024:PLCD1 protein, human; D054803:Phospholipase C delta; C518025:Plcd1 protein, mouse