The retinoblastoma tumor suppressor protein (pRb) regulates the cell cycle, facilitates differentiation, and restrains apoptosis. Furthermore, dysfunctional pRb is thought to be involved in the development of most human malignancies. Many of the functions of pRb are mediated by its regulation of the E2F transcription factors. To understand the structural basis for this regulation, we have deter...

Phosphorylation and dephosphorylation of the retinoblastoma protein, pRB, play a role in the control of cell cycle progression and expression of differentiation in eukaryotic cells. The regulation of pRB level and phosphorylation state was investigated during the induction of differentiation of murine erythroleukemia cells (MELC) by the chemical agent hexamethylene bisacetamide (HMBA). In MELC,...

Rb1 is essential for normal embryonic development, as null mice die in midgestation with widespread unscheduled cell proliferation. Rb1 protein (pRb) mediates cell cycle control by binding E2F transcription factors and repressing expression from E2F-dependent promoters. An increasing amount of evidence suggests that pRb loss also compromises cellular differentiation. Since differentiation is of...

The retinoblastoma protein (pRb) is required for cell-cycle exit of embryonic mammalian hair cells but is not required for hair cell fate determination and early differentiation, and this provides a strategy for hair cell regeneration by manipulating the pRb pathway. To reveal the mechanism of pRb functional modification in the inner ear, we compared the effects of attenuated pRb phosphorylatio...

Permeable reactive barriers (PRBs) consist of a labile carbon source that is positioned to intercept nitrate-laden groundwater to prevent eutrophication. Decomposition of carbon in the PRB drives groundwater anoxic, fostering microbial denitrification. Such PRBs are an ideal habitat to examine microbial community structure under high-nitrate, carbon-replete conditions in coastal aquifers. We ex...

Neuronal death evoked by DNA damage requires cyclin-dependent kinase 4 (Cdk4) and 6 activity and is accompanied by elevation of cyclin D1-associated kinase activity. Because Cdk4/6 phosphorylates retinoblastoma protein (pRb) family members that then modulate the transcriptional activity of E2F/DP1 complexes, we examined the involvement of these components in DNA damage-evoked neuronal death. Ca...

p16CDKN2 specifically binds to and inhibits the cyclin-dependent kinases CDK4 and CDK6, which function as regulators of cell cycle progression in G1 by contributing to the phosphorylation of the retinoblastoma protein (pRB). Human cell lines lacking functional pRB contain high levels of p16 RNA and protein, suggesting a negative feedback loop by which pRB might regulate p16 expression in late G...

The retinoblastoma protein, pRb, controls entry into the S phase of the cell cycle and acts as a tumor suppressor in many tissues. Re-introduction of pRb into tumor cells lacking this protein results in growth arrest, due in part to transcriptional repression of genes required for S phase. Several studies suggest that pRb may also be involved in terminal cell cycle exit as a result of the insti...

This work aims to shed light on the scale-up a combined electrokinetic soil flushing process (EKSF) with permeable reactive barriers (PRB) for treatment of spiked clopyralid. To do this, remediation tests at lab (3.45 L), bench (175 L) and pilot (1400 scales have been carried out. The PRB selected was made merged particles zero valent iron (ZVI) granular activated carbon (GAC). Results show tha...

OBJECTIVE The retinoblastoma protein family (pRb, p130, p107) plays a central role in the regulation of cell cycle progression. Surprisingly, loss of pRb in the beta-cell has no discernible effect on cell cycle control. Therefore, we explored the effects of individual loss of either p130 or p107 in addition to the simultaneous loss of both pRb/p130 on the beta-cell. RESEARCH DESIGN AND METHOD...