Control of expression of PLCbeta1 by LAC repressor system: relationship between nuclear PLCbeta1 overexpression and growth factor stimulation.
Swiss 3T3 cells have a nuclear phosphoinositide signalling system which is under the control of insulin-like growth factor I (IGF-I) and acts separately from that at the plasma membrane. By using the Lac repressor system we were able both to obtain the inducible overexpression of phospholipase C beta1 (PLC beta1) and to determine its subcellular localisation and partitioning. Moreover, by comparing the level of expression at the nucleus and the percentage of cells actively incorporating bromodeoxyuridine (BrdU) in S phase it has strengthened the issue of the importance of this PLC in the onset of DNA synthesis mediated by IGF-I. In addition, this system appears to be a very powerful tool for further analysis of the downstream events following the activation of nuclear PLC beta1.
Billi
A M
AM
Institute of Human Anatomy, University of Bologna, Bologna, 40126, Italy.
Matteucci
A
A
Faenza
I
I
Manzoli
L
L
Rubbini
S
S
Gilmour
R S
RS
Rhee
S G
SG
Cocco
L
L
D016475:3T3 Cells; D000818:Animals; D001426:Bacterial Proteins / Q000096:biosynthesis / Q000378:metabolism*; D001839:Bombesin / Q000494:pharmacology; D002453:Cell Cycle / Q000187:drug effects*; D002467:Cell Nucleus / Q000201:enzymology*; D029968:Escherichia coli Proteins; D015971:Gene Expression Regulation, Enzymologic / Q000187:drug effects; D005822:Genetic Vectors; D006133:Growth Substances / Q000494:pharmacology*; D007334:Insulin-Like Growth Factor I / Q000494:pharmacology; D007527:Isoenzymes / Q000096:biosynthesis*; D056968:Lac Repressors; D051379:Mice; D054799:Phospholipase C beta; D010982:Platelet-Derived Growth Factor / Q000494:pharmacology; D011994:Recombinant Proteins / Q000096:biosynthesis / Q000378:metabolism; D012097:Repressor Proteins / Q000096:biosynthesis / Q000378:metabolism*; D016196:S Phase; D013539:Simian virus 40; D014162:Transfection; D010738:Type C Phospholipases / Q000096:biosynthesis*
D001426:Bacterial Proteins; D029968:Escherichia coli Proteins; D006133:Growth Substances; D007527:Isoenzymes; D056968:Lac Repressors; D010982:Platelet-Derived Growth Factor; D011994:Recombinant Proteins; D012097:Repressor Proteins; D007334:Insulin-Like Growth Factor I; D010738:Type C Phospholipases; D054799:Phospholipase C beta; C518034:Plcb1 protein, mouse; D001839:Bombesin