Inhibition of alanyl-aminopeptidase suppresses the activation-dependent induction of glycogen synthase kinase-3beta (GSK-3beta) in human T cells.
Inhibition of alanyl-aminopeptidase (APN, CD13) gene expression or enzymatic activity compromises T cell proliferation and function. Molecular mechanisms mediating these effects are not known as yet. Recently, we found the expression of the proto-oncogen Wnt-5a to be strongly affected by APN-inhibition. Wnt-5a and other members of the Wnt family of secreted factors are implicated in cell growth and differentiation. Here, we analyzed by quantitative RT-PCR and immunoblotting the expression in mitogen-activated T cells of a major constituent of the Wnt-5a pathway, glycogen synthase kinase-3beta (GSK-3beta). T cell activation by phytohaemagglutinin or pokeweed mitogen results in a strong increase of GSK-3beta mRNA amounts. At the protein level, we observed an up-regulation of both GSK-3beta and phosphorylated GSK-3beta. This induction-dependent increase of GSK-3beta is markedly reduced in response to inhibitors of alanyl-aminopeptidase, actinonin, leuhistin, and RB3014. These findings may provide a rational for the growth inhibition resulting from a diminished expression or activity of alanyl aminopeptidase.
Lendeckel
U
U
Institute of Experimental Internal Medicine, Center of Internal Medicine, Otto-von-Guericke University of Magdeburg, Germany. uw.lendeckel@medizin.uni-magdeburg.de
Scholz
B
B
Arndt
M
M
Frank
K
K
Spiess
A
A
Chen
H
H
Roques
B P
BP
Ansorge
S
S
D000596:Amino Acids / Q000494:pharmacology; D015153:Blotting, Western; D018826:CD13 Antigens / Q000037:antagonists & inhibitors* / Q000378:metabolism; D017871:Calcium-Calmodulin-Dependent Protein Kinases / Q000235:genetics / Q000378:metabolism*; D002478:Cells, Cultured; D004790:Enzyme Induction / Q000187:drug effects; D038362:Glycogen Synthase Kinase 3; D038341:Glycogen Synthase Kinases; D006801:Humans; D006877:Hydroxamic Acids / Q000494:pharmacology; D007093:Imidazoles / Q000494:pharmacology; D008213:Lymphocyte Activation / Q000187:drug effects; D010766:Phosphorylation / Q000187:drug effects; D010768:Phosphoserine / Q000378:metabolism; D010835:Phytohemagglutinins / Q000494:pharmacology; D011043:Pokeweed Mitogens / Q000494:pharmacology; D011480:Protease Inhibitors / Q000494:pharmacology*; D011518:Proto-Oncogene Proteins / Q000502:physiology; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D015398:Signal Transduction / Q000187:drug effects; D013601:T-Lymphocytes / Q000166:cytology / Q000187:drug effects* / Q000201:enzymology*; D051153:Wnt Proteins; D000071818:Wnt-5a Protein
D000596:Amino Acids; D006877:Hydroxamic Acids; D007093:Imidazoles; D010835:Phytohemagglutinins; D011043:Pokeweed Mitogens; D011480:Protease Inhibitors; D011518:Proto-Oncogene Proteins; D012333:RNA, Messenger; C085389:WNT5A protein, human; D051153:Wnt Proteins; D000071818:Wnt-5a Protein; C069912:leuhistin; D010768:Phosphoserine; D038341:Glycogen Synthase Kinases; D017871:Calcium-Calmodulin-Dependent Protein Kinases; D038362:Glycogen Synthase Kinase 3; D018826:CD13 Antigens; C010531:actinonin