Introduction: Iron deficiency anemia represents 3rd largest disease burden, with an estimated 6.9 billion disability-adjusted life years. Iron-fortified cereals (IFIC) can contribute substantially in preventing iron deficiency anemia and maintaining an adequate body iron status.
View Article and Find Full Text PDFWe previously identified Waf1 Cip1 stabilizing protein 39 (WISp39) as a binding partner for heat shock protein 90 (Hsp90). We now report that WISp39 has an essential function in the control of directed cell migration, which requires WISp39 interaction with Hsp90. WISp39 knockdown (KD) resulted in the loss of directional motility of mammalian cells and profound changes in cell morphology, including the loss of a single leading edge.
View Article and Find Full Text PDFSelf/non-self discrimination characterizes immunity and allows responses against pathogens but not self-antigens. Understanding the principles that govern this process is essential for designing autoimmunity treatments. p21 is thought to attenuate autoreactivity by limiting T cell expansion.
View Article and Find Full Text PDFEndogenous mouse mammary tumor proviruses (MMTV; Mtv loci) deletes Vbeta6 expressing T cells in the thymus of Mtv-7(+) DBA/2 (H2(d)) mice through negative selection. We found that in Mtv-7(-) BALB/c (H2(d)) mice, Vbeta6 is a dominant V gene used in T cell responses to an 18 amino acid long peptide antigen: EYKEYAEYAEYAEYAEYA [abbreviated as K5 or EYK(EYA)(5)]. It was therefore surprising to find that despite the deletion of Vbeta6+ T cells, vigorous K5 specific T cell responses that use Vbeta6 can be raised in DBA/2 mice.
View Article and Find Full Text PDFSeveral regulatory proteins control cell cycle progression. These include Emi1, an anaphase-promoting complex (APC) inhibitor whose destruction controls progression through mitosis to G1, and p21(WAF1), a cyclin-dependent kinase (CDK) inhibitor activated by DNA damage. We have analyzed the role of p21(WAF1) in G2-M phase checkpoint control and in prevention of polyploidy after DNA damage.
View Article and Find Full Text PDFThe mechanism underlying the chemopreventive effects of the non-steroidal anti-inflammatory drug sulindac remains unclear. Its active metabolite, sulindac sulfide, induces cell cycle arrest as well as apoptosis in mammalian cell lines. We now show that in murine thymocytes, sulindac sulfide-induced cell death is p53, bax, Fas, and FasL independent.
View Article and Find Full Text PDFp21(WAF1/CIP1), a cyclin-dependent kinase inhibitor and a critical regulator of cell cycle, is controlled transcriptionally by p53-dependent and -independent mechanisms and posttranslationally by the proteasome. We have identified WISp39, a tetratricopeptide repeat (TPR) protein that binds p21. WISp39 stabilizes newly synthesized p21 protein by preventing its proteasomal degradation.
View Article and Find Full Text PDFp21WAF1 was originally identified as a protein that binds and inhibits cyclin-dependent kinases (CDKs). p21WAF1 is recognized to have at least two separate roles-first as a CDK inhibitor, and second as an inhibitor of PCNA, an accessory protein of DNA polymerase delta. p21WAF1 plays a critical role in the cellular response to DNA damage.
View Article and Find Full Text PDFRb (retinoblastoma protein) inhibits E2F-1-induced cell death. We now show that the ability of Rb to inhibit E2F-1-induced cell death is dependent on a functional LXCXE-binding site in Rb, thereby suggesting that proteins that bind the LXCXE-binding site in Rb may regulate the anti-apoptotic activity of Rb. HDAC1, an LXCXE protein that plays a critical role in Rb-mediated transcription repression, abrogates the effect of Rb on E2F-1-induced cell death.
View Article and Find Full Text PDFUV or g irradiation mediated DNA damage activates p53 and induces cell cycle arrest. Induction of cyclin dependent kinase inhibitor p21WAF1 by p53 after DNA damage plays an important role in cell cycle arrest after gamma irradiation. The p53 mediated cell cycle arrest has been postulated to allow cells to repair the DNA damage.
View Article and Find Full Text PDFp53-mediated increase in cyclin-dependent kinase inhibitor p21(WAF1) protein is thought to be the major mediator of cell cycle arrest after DNA damage. Previously p21 protein levels have been reported to increase or to decrease after UV irradiation. We show that p21 protein is degraded after irradiation of a variety of cell types with low but not high doses of UV.
View Article and Find Full Text PDFThe five subunit replication factor C (RF-C) complex plays a critical role in DNA elongation. We find that the large subunit of RF-C (RF-Cp145) is phosphorylated in vivo whereas the smaller RF-C subunits are not phosphorylated. The phosphorylation of endogenous RFCp145 is modulated in a cell cycle-dependent manner.
View Article and Find Full Text PDFNucleic Acids Res
September 2003
Replication factor C (RF-C) complex binds to DNA primers and loads PCNA onto DNA, thereby increasing the processivity of DNA polymerases. We have previously identified a distinct region, domain B, in the large subunit of human RF-C (RF-Cp145) which binds to PCNA. We show here that the functional interaction of RF-Cp145 with PCNA is regulated by cdk-cyclin kinases.
View Article and Find Full Text PDFalpha(v)-Integrin antagonists block neovascularization in various species, whereas 20% of alpha(v)-integrin null mice are born with many normal looking blood vessels. Given that blockade of alpha(v)-integrins during angiogenesis induces p53 activity, we utilized p53 null mice to elucidate whether loss of p53 can compensate for alpha(v)-integrin function in neovascularization of the retina. Murine retinal vascularization was inhibited by systemic administration of an alpha(v)-integrin antagonist.
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