Stem cells persist throughout life in diverse tissues by undergoing self-renewing divisions. Self-renewal capacity declines with age, partly because of increasing expression of the tumor suppressor p16(Ink4a). We discovered that the Hmga2 transcriptional regulator is highly expressed in fetal neural stem cells but that expression declines with age. This decrease is partly caused by the increasi...

In this study, the effect of fibronectin on the neurite outgrowth from embryoid bodies (EBs) in neurodifferentiated embryonal carcinoma P19 cells was examined. The neurite outgrowth on fibronectin was maintained for a longer time in comparison with those on collagen or laminin. Quantitative RT-PCR revealed that mRNA level corresponding to sonic hedgehog (Shh) in neurodifferentiated P19 cells wa...

Sirtuin 1 (SIRT1) is known to suppress differentiation of pluripotent/multipotent cells and neural progenitor cells into neurons by blocking activation of transcription factors critical for neurogenesis. EX-527 is a highly selective and potent inhibitor against SIRT1 and has been used as a chemical probe that modulates SIRT1-associated biological processes. However, the effect of EX-527 on neur...

Reduced DNA repair has been linked to an increased risk of cutaneous malignant melanoma, but insights into the molecular mechanisms of that link are scarce. The INK4a/ARF (CDKN2a) locus, which codes for the p16 and p19 proteins, is often mutated in sporadic and familial malignant melanoma, but it has not been directly associated with reduced DNA repair. We transfected unirradiated mouse fibrobl...

P19 cells, a mouse embryonal carcinoma line, can be induced to differentiate into neurons. After induction, however, only a small subpopulation of cells develop as neurons, suggesting that equipotent cells adopt different cell fates. In invertebrate systems, the lin-12-Notch family of genes is thought to control the choice of cell fate. We have therefore asked whether activation of murine Notch...

Wnt/beta-catenin signaling plays a critical role in embryonic myogenesis. Here we show that, in P19 embryonic carcinoma stem cells, Wnt/beta-catenin signaling initiates the myogenic process depends on beta-catenin-mediated relief of I-mfa (inhibitor of MyoD Family a) suppression of myogenic regulatory factors (MRFs). We found that beta-catenin interacted with I-mfa and that the interaction was ...

The mouse p19(Arf) protein has both p53-dependent and p53-independent tumor-suppressive activities. Arf triggers sumoylation of many cellular proteins, including Mdm2 and nucleophosmin (NPM/B23), with which p19(Arf) physically interacts in vivo, and this occurs equally well in cells expressing or lacking functional p53. In an Arf-null NIH 3T3 cell derivative (MT-Arf cells) engineered to reexpre...

BACKGROUND We have previously shown marked upregulation of the mRNA and corresponding protein for the cellular motor molecule myosin VI (Myo6) after an extremely traumatic stress experience, along with a delayed decrease in 5-bromo-2'-deoxyuridine incorporation in the murine hippocampus, a brain structure believed to undergo adult neurogenesis. In this study, we investigated the role of Myo6 in...

In this study, the effect of fibronectin on the neurite outgrowth from embryoid bodies (EBs) in neurodifferentiated embryonal carcinoma P19 cells was examined. The neurite outgrowth on fibronectin was maintained for a longer time in comparison with those on collagen or laminin. Quantitative RT-PCR revealed that mRNA level corresponding to sonic hedgehog (Shh) in neurodifferentiated P19 cells wa...