Expression of alkaline phosphatase in murine lymphoma cells.
Alkaline phosphatase (ALP) was secreted and expressed at the cell surface of the lymphoma A/63-2 cell line but not on another clone A/63-1 deriving from a single thymoma (A/63) induced by a wild-type Abelson-Moloney viral complex. The enzyme was heat-sensitive and strongly inhibited by L-p-bromotetramisole and L-homoarginine but not by L-phenylalanine. All these data indicated that this enzyme was most likely identical to the L/B/K ALP isoenzyme. Southern blot analysis showed that neither amplification nor polymorphism were responsible for the high expression of the ALP gene observed in A/63-2 cells. On the opposite, the mRNA transcripts of ALP were only detected in A/63-2 cells indicating that a modulation of the ALP gene transcription occurred which could be due to the insertion of the v-abl gene within or near the 5'-flanking region of the ALP promotor in A/63-2 cells. Butyrate strongly increased both the secretion and the expression of the enzyme on A/63-2 cell surface. This induction was strongly inhibited by cordycepin, an RNA biosynthesis inhibitor, and at a lesser degree by cycloheximide, a translation inhibitor suggesting that butyrate induction occurs both at the transcriptional and the translational level.
Harb
J
J
U.F.R. de Médecine, Laboratoire de Biochimie Médicale (CJF INSERM 90-11), Nantes, France.
Vavasseur
F
F
Chadéneau
C
C
Denis
M
M
Meflah
K
K
D000469:Alkaline Phosphatase / Q000235:genetics* / Q000378:metabolism; D000818:Animals; D015139:Blotting, Southern; D002460:Cell Line; D003001:Cloning, Molecular; D004273:DNA, Neoplasm / Q000235:genetics / Q000302:isolation & purification; D007700:Kinetics; D008223:Lymphoma / Q000201:enzymology* / Q000235:genetics; D051379:Mice; D043265:Phosphatidylinositol Diacylglycerol-Lyase; D010727:Phosphoric Diester Hydrolases / Q000378:metabolism; D012334:RNA, Neoplasm / Q000235:genetics / Q000302:isolation & purification; D015183:Restriction Mapping; D013945:Thymoma / Q000201:enzymology / Q000235:genetics; D013953:Thymus Neoplasms / Q000201:enzymology / Q000235:genetics; D014158:Transcription, Genetic
D004273:DNA, Neoplasm; D012334:RNA, Neoplasm; D000469:Alkaline Phosphatase; D010727:Phosphoric Diester Hydrolases; D043265:Phosphatidylinositol Diacylglycerol-Lyase