Phospholipase activity is modulated by c-Fos through substrate expansion and hyperpolarization.

GRACIELA ADRIANA BORIOLI; CAPUTTO BL,; MAGGIO B.,

FEBS LETTERS

Año: 2004 vol. 570 p. 82 - 82

0014-5793

span lang="en" style="font-size: 12pt; font-family: Arial;">c-Fos, a component of AP-1 transcription factors, has been shown to have marked amphitropic properties and to regulate phospholipase activity against lipid monolayers. In agreement with its high surface activity, it has also been found to associate to membranes of the endoplasmic reticulum and to activate phospholipid metabolism in vivo. All these findings point to an involvement of this oncoprotein within a membrane environment. We have previously shown that c-Fos modulates in different manners the activity of phospholipase A2 and phospholipase C against monolayers of dilauroylphosphatidylcholine (PC). In this work we have studied the possible molecular mechanism underlying the phosphohydrolytic modulation. Our results show that c-Fos expands and hyperpolarizes PC, indicating that its effects on these enzymatic