The NAD-dependent histone deacetylase Sirt1 antagonizes p53 transcriptional activity to regulate cell-cycle progression and apoptosis. We have identified a ubiquitin-specific peptidase, USP22, one of the 11 death-from-cancer signature genes that are critical in controlling cell growth and death, as a positive regulator of Sirt1. USP22 interacts with and stabilizes Sirt1 by removing polyubiquiti...

Until recently, the only means by which electrical activity was believed to initiate retrograde signals was via postsynaptic events: modulated synthesis or release of trophic factors. We have evidence in chick embryos for a presynaptic initiation of retrograde signals from the retina to the isthmo-optic nucleus, which is known to undergo 55% neuron death between embryonic days 12 and 17 and to ...

Microglia are known to invade the mammalian spinal cord (SC) at an early embryonic stage. While the mechanisms underlying this early colonization of the nervous system are still unknown, we recently found that it is associated, at least partially, with the ability of microglia to proliferate at the onset of motoneuron developmental cell death and of synaptogenesis in mouse embryo (E13.5). In vi...

toxoplasmosis, caused by toxoplasma gondii (t. gondii), is an economically important disease of livestock, especially sheep and goats, where it can cause early embryonic death and resorption, fetal death and mummification, abortion, stillbirth, and neonatal death.cats are the main reservoir for the toxoplasmosis which can contaminate the environments of other animal and human beings by their fa...

We have generated a murine embryonic stem cell line constitutively expressing L1 at all stages of neural differentiation to investigate the effects of L1 overexpression on stem cell proliferation, migration, differentiation, cell death, and ability to influence drug-induced rotation behavior in an animal model of Huntington's disease. L1-transfected cells showed decreased cell proliferation in ...

In Drosophila, the Toll pathway establishes the embryonic dorsoventral axis and triggers innate immune responses to infection. The transmembrane receptor Toll acts through three death domain-containing proteins, the kinase Pelle and the adapters Tube and MyD88, in signaling to downstream NF-kappaB-like transcription factors. Here, we delineate the critical events in the earliest stages of Toll ...

The lymphoid cells of embryonic bursal follicles are engaged in rapid growth and preimmune diversification of immunoglobulin genes. Disruption of follicular architecture by mechanical dispersion of these cells in short-term tissue culture was accompanied by continued cell division and extensive cell death by apoptosis. Apoptosis was suppressed in parallel cultures of intact follicles. gamma Rad...

Although animals eliminate apoptotic cells using macrophages, plants use cell corpses throughout development and disassemble cells in a cell-autonomous manner by vacuolar cell death. During vacuolar cell death, lytic vacuoles gradually engulf and digest the cytoplasmic content. On the other hand, acute stress triggers an alternative cell death, necrosis, which is characterized by mitochondrial ...

The Snail zinc-finger transcription factors trigger epithelial-mesenchymal transitions (EMTs), endowing epithelial cells with migratory and invasive properties during both embryonic development and tumor progression. During EMT, Snail provokes the loss of epithelial markers, as well as changes in cell shape and the expression of mesenchymal markers. Here, we show that in addition to inducing dr...

Necroptosis is a well-known form of caspase-independent cell death. Necroptosis can be triggered by various extrinsic stimuli, including death ligands in the presence of receptorinteracting protein kinase 3 (RIPK3), a key mediator of necroptosis induction. Our recent studies have revealed that C-terminus HSC-70 interacting protein (CHIP), an E3 ligase, can function as an inhibitor of necroptosi...