The
tuftelin protein isoforms undergo post-translation modifications, and are ubiquitously expressed in various tissues in embryos, adults, and
tumors. Developmental and pathological studies suggested an apparent correlation between
oxygen deprivation and
tuftelin expression. The aim of the study was therefore to investigate the effect of a pathological insult (
hypoxia) and a physiological
growth factor (
NGF), which antagonistically regulate HIF1 expression, on
tuftelin expression using the neuronal PC12 cell model. In the present study, we first demonstrated the expression of
tuftelin in PC12 cells, providing an experimental system to investigate the pathophysiological role of
tuftelin. Furthermore, we demonstrated the induction of
tuftelin during
hypoxia by
oxygen deprivation and during chemical
hypoxia by
cobalt chloride. Down-regulation of HIF1α
mRNA blocked
hypoxia-induced HIF1α expression, and reduced by 89%
hypoxia-induced
tuftelin expression. In mice,
intraperitoneal injection of
cobalt chloride significantly induced
tuftelin mRNA and
protein expression in the brain. During
NGF-mediated PC12 differentiation,
tuftelin expression was significantly induced in correlation with neurite outgrowth. This induction was partially blocked by
K252a, a selective antagonist of the
NGF receptor TrkA, indicating the involvement of the TrkA-signaling pathways in
tuftelin induction by
NGF. Revealing the physiological role of
tuftelin will clarify mechanisms related to the "hypoxic genome," and
NGF-induced neurotrophic and angiogenic effects.