Aluminium differentially modifies lipid metabolism from the phosphoinositide pathway in Coffea arabica cells.
The effect of aluminium (Al) on phosphoinositide-specific phospholipase C (PLC) and lipid kinase activities was examined in a cellular suspension of coffee. Two main effects were seen when cells were treated with AlCl3. In periods as short as 1 minute, Al-exposed cells increased the activity of PLC and IP3 formation up to two fold. Over longer periods PLC activity was inhibited by more than 50%. The activity of phosphatidylinositol 4-kinase (Pl 4-K), phosphatidylinositol phosphate 5-kinase (PIP 5-K) and diacylglycerol kinase increased when cells were incubated in the presence of different concentrations of AlCl3. The present study reports for the first time that Al may have different effects on the Pl-signaling pathway depending on the time of exposure. Our results strongly support the hypothesis that Al disrupts the metabolism of membrane phospholipids regulating not only PLC but also other enzymes that have key roles in signal-transduction pathways.
Martínez-Estévez
Manuel
M
Unidad de Bioquímica y Biología Molecular de Plantas, Centro de Investigación Científica de Yucatán, CP 97200, Mérida, Yucatán, México.
Racagni-Di Palma
Graciela
G
Muñoz-Sánchez
J Armando
JA
Brito-Argáez
Ligia
L
Loyola-Vargas
Víctor M
VM
Hernández-Sotomayor
S M
SM
D019870:1-Phosphatidylinositol 4-Kinase / Q000378:metabolism; D000077410:Aluminum Chloride; D017607:Aluminum Compounds / Q000494:pharmacology*; D002478:Cells, Cultured; D002712:Chlorides / Q000494:pharmacology*; D040503:Coffea / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D019852:Diacylglycerol Kinase / Q000378:metabolism; D050356:Lipid Metabolism; D019869:Phosphatidylinositol 3-Kinases / Q000378:metabolism; D010716:Phosphatidylinositols / Q000378:metabolism*; D017853:Phosphotransferases (Alcohol Group Acceptor) / Q000378:metabolism; D015398:Signal Transduction / Q000187:drug effects; D013997:Time Factors; D010738:Type C Phospholipases / Q000378:metabolism
D017607:Aluminum Compounds; D002712:Chlorides; D010716:Phosphatidylinositols; D000077410:Aluminum Chloride; D019869:Phosphatidylinositol 3-Kinases; D017853:Phosphotransferases (Alcohol Group Acceptor); D019852:Diacylglycerol Kinase; D019870:1-Phosphatidylinositol 4-Kinase; C020077:1-phosphatidylinositol-4-phosphate 5-kinase; D010738:Type C Phospholipases