Productive infection of human T lymphocytes by HIV-1 is dependent upon proliferation of the infected cell. Nonproliferating quiescent T cells can be infected by HIV-1 and harbor the virus in an inactive state until subsequent mitogenic stimulation. We use a modification of the polymerase chain reaction method, which is both sensitive and quantitative, to demonstrate that HIV-1 DNA synthesis is ...

Satellite cells are the resident stem cells of adult skeletal muscle. To date though, there is a paucity of native markers that can be used to easily identify quiescent satellite cells, with Pax7 probably being the best that is currently available. Here we have further characterized a number of recently described satellite cell markers, and also describe novel ones. Caveolin-1, integrin alpha7 ...

Neural stem cells (B1 astrocytes; NSCs) in the adult ventricular-subventricular-zone (V-SVZ) originate in the embryo. Surprisingly, recent work has shown that B1 cells remain largely quiescent. They are reactivated postnatally to function as primary progenitors for neurons destined for the olfactory bulb and some corpus callosum oligodendrocytes. The cellular and molecular properties of quiesce...

The vast majority of lymphocytes in vivo persist in a quiescent state. These resting lymphocytes are maintained through a cellular program that suppresses apoptosis. We show here that quiescent PBMC, but not activated PBMC or transformed lymphocytes, die in the presence of highly specific post-proline aminodipeptidase inhibitors. This form of death has the hallmarks of apoptosis, such as phosph...

We detected the second historical outburst of the 1920 nova IM Nor. Accurate astrometry of the outbursting object revealed the true quiescent counterpart having a magnitude of R=17.0 mag and B=18.0 mag. We show that the quiescent counterpart shows a noticeable variation. From the comparison of light curves and spectroscopic signatures, we propose that IM Nor and CI Aql comprise a new class of r...

Quiescent stem cells contribute to tissue homeostasis and repair in adult mammals. We identified a tumor suppressor PRDM2, as an epigenetic regulator induced in quiescent muscle stem cells as well as in cultured quiescent myoblasts. To delineate the functions of PRDM2 in muscle cells, we compared the gene expression profiles of control and PRDM2 knockdown myoblasts in growing, differentiating a...

Continuous intracellular recording of membrane potential with microelectrodes in BSC-1 epithelial cells has been used to study the early ionic effects of the interaction of mitogens with cell surface receptors. Initial results show that (i) there is no significant difference in membrane potential between growing and quiescent cells, (ii) addition of epidermal growth factor or serum to quiescent...

Regeneration of damaged tissues typically requires a population of active stem cells. How damaged tissue is regenerated in quiescent tissues lacking a stem cell population is less well understood. We used a genetic screen in the developingDrosophilamelanogastereye to investigate the mechanisms that trigger quiescent cells to re-enter the cell cycle and proliferate in response to tissue damage. ...

The majority of cancer stem cells exist in the G0, or quiescent phase of the cell cycle. However, the cells can escape quiescence following routine radiotherapy and chemotherapy, resulting in tumor recurrence. Presently, achieving the accurate regulation of cancer stem cell growth in order to study a specific state, including the quiescent (mostly G0 or G1 phase), proliferative (mostly S phase)...

Quiescence or dormancy plays an important role in biological systems, from spore formation in bacteria to predator-prey cycles. In a mathematical framework, quiescence is modeled by diffusive coupling of the active dynamics to quiescent phases. Although coupling a given vector field to the zero field may appear simple at first glance, quiescent phases have biologically relevant effects which ca...