Modification of protein sub-nuclear localization by synthetic phosphoinositides: evidence for nuclear phosphoinositide signaling mechanisms.
PtdInsPs are critical signaling molecules that regulate diverse cellular functions. One method to study PtdInsP biology involves using synthetic PtdInsP analogs to activate endogenous PtdInsP-mediated events in living cells. Such methodology has been successfully employed to explore the role of several PtdInsP-biological outcomes in the cytoplasm. However, this strategy has not previously been used to examine the function of PtdInsPs in the nucleus of live cells, primarily because there has not been a well-defined PtdInsP-binding protein to provide functional nuclear readouts. Here we have shown that synthetic PtdIns(5)P analogs access and function in the nucleus. We have found that these molecules modify the sub-nuclear localization of PHD finger-containing proteins in live cells and in real time. This work demonstrates that synthetic PtdInsPs and PtdInsP derivatives may be powerful tools for probing nuclear PtdInsP functions. Finally, our work supports a model that endogenous PtdInsPs regulate sub-nuclear localization and function of endogenous nuclear PtdInsP-binding proteins.
Gozani
Or
O
Department of Cell Biology, Harvard Medical School, Boston, MA 02115, USA. ogozani@stanford.edu
Field
Seth J
SJ
Ferguson
Colin G
CG
Ewalt
Mark
M
Mahlke
Christopher
C
Cantley
Lewis C
LC
Prestwich
Glenn D
GD
Yuan
Junying
J
D000818:Animals; D001896:Boron Compounds; D002460:Cell Line; D002467:Cell Nucleus / Q000502:physiology* / Q000648:ultrastructure; D018398:Homeodomain Proteins / Q000502:physiology*; D051379:Mice; D008807:Mice, Inbred BALB C; D041681:NIH 3T3 Cells; D019913:Nuclear Localization Signals / Q000502:physiology; D018129:Phosphatidylinositol Phosphates / Q000378:metabolism / Q000502:physiology*; D018160:Receptors, Cytoplasmic and Nuclear / Q000502:physiology*; D015398:Signal Transduction / Q000502:physiology*; D025521:Tumor Suppressor Proteins / Q000502:physiology*
C095489:4,4-difluoro-4-bora-3a,4a-diaza-s-indacene; D001896:Boron Compounds; D018398:Homeodomain Proteins; C444654:ING2 protein, human; D019913:Nuclear Localization Signals; D018129:Phosphatidylinositol Phosphates; D018160:Receptors, Cytoplasmic and Nuclear; D025521:Tumor Suppressor Proteins; C113567:phosphatidylinositol 5-phosphate