Kimberly D. Klarmann

Learn More
The (histone) deacetylase Sirt1 is a mediator of genomic and epigenetic maintenance, both of which are critical aspects of stem cell homeostasis and tightly linked to their functional decline in aging and disease. We show that Sirt1 ablation in adult hematopoietic stem and progenitor cells (HSPCs) promotes aberrant HSPC expansion specifically under(More)
Id1 is frequently overexpressed in many cancer cells, but the functional significance of these findings is not known. To determine if Id1 could contribute to the development of hematopoietic malignancy, we reconstituted mice with hematopoietic cells overexpressing Id1. We showed for the first time that deregulated expression of Id1 leads to a(More)
The interferon-inducible p200 (IFI-200) family of proteins is among the numerous gene products induced by interferons (IFNs), which are important regulators of cell growth, immunomodulation and host resistance to tumors and viral infections. The members of this family of proteins are highly homologous to one another and consist of five murine proteins(More)
CCAAT enhancer binding protein-alpha (C/EBPalpha) inhibits proliferation in multiple cell types; therefore, we evaluated whether C/EBPalpha-deficient hematopoietic progenitor cells (HPCs) have an increased proliferative potential in vitro and in vivo. In this study we demonstrate that C/EBPalpha(-/-) fetal liver (FL) progenitors are hyperproliferative, show(More)
Mouse knockouts of Cdk2 and Cdk4 have demonstrated that, individually, these genes are not essential for viability. To investigate whether there is functional redundancy, we have generated double knockout (DKO) mice. Cdk2-/- Cdk4-/- DKOs die during embryogenesis around E15 as a result of heart defects. We observed a gradual decrease of Retinoblastoma(More)
Lymphotoxin alpha (LTalpha) can exist in soluble form and exert tumor necrosis factor (TNF)-like activity through TNF receptors. Based on the phenotypes of knockout (KO) mice, the physiological functions of LTalpha and TNF are considered partly redundant, in particular, in supporting the microarchitecture of the spleen and in host defense. We exploited(More)
Inhibitors of DNA binding (Id) family members are key regulators of cellular differentiation and proliferation. These activities are related to the ability of Id proteins to antagonize E proteins and other transcription factors. As negative regulators of E proteins, Id proteins have been implicated in lymphocyte development. Overexpression of Id1, Id2, or(More)
Pancreatic cancer is the fourth leading cause of cancer-related mortality in the world. Pancreatic cancer can be localized, locally advanced, or metastatic. The median 1- and 5-year survival rates are 25% and 6%, respectively. Epigenetic modifications such as DNA methylation play a significant role during both normal human development and cancer(More)
Toll-like receptor 4 (Tlr4) has a pivotal role in innate immune responses, and the transcription factor CCAAT/enhancer binding protein delta (C/EBPδ, Cebpd) is a Tlr4-induced gene. Here we identify a positive feedback loop in which C/EBPδ activates Tlr4 gene expression in macrophages and tumour cells. In addition, we discovered a negative feedback loop(More)
Obesity is a major health concern that contributes to the development of diabetes, hyperlipidemia, coronary artery disease, and cancer. Id proteins are helix-loop-helix transcription factors that regulate the proliferation and differentiation of cells from multiple tissues, including adipocytes. We screened mouse tissues for the expression of Id1 and found(More)