Human Neonatal Keratinocytes Have Very High Levels of Cellular Vitamin A-Binding Proteins

Since cellular retinol- and retinoic acid-binding proteins (CRBP and CRABP) mediate the effects of vitamin A on epidermal differentiation, the levels of these binding proteins were measured in the epidermal and dermal layers of newborn, human foreskin as well as in primary cultures of keratinocytes and fibroblasts from these layers. ligand binding assays w3ith saturating concentrations of all trans-[3H]retinol or of all trans-[11-3H]retinoic acid were used to quantitate amounts of binding proteins in cytosols prepared form these skin layers or cultured cells. The epidermal levels of CRABP and CRBP (60.9 ± 14.4 and 7.3 ± 1.7 pmol per mg cytosol protein, respectively) were markedly higher than that reported for adult epidermis but wer comparable to levels in keratinocytes cultured from neonatal foreskin epidermis (61.8 ± 7.8 and 10.7 ± 2.5, respectively). The levels of CRABP were much lower in the foreskin dermis than in the epidermis and the levels measured in the fibroblasts cultured form this dermis were consistent with the dermal levels. however, CRBP levels in cultured dermal fibroblasts were very low and could not account for the dermal CRBP levels, suggesting that another dermal cell type has high levels of CRBP

Identification and localization of a caleosin in olive (Olea europaea L.) pollen during in vitro germination

In plant organs and tissues, the neutral storage lipids are confined to discrete spherical organelles called oil bodies. Oil bodies from plant seeds contain 0.6–3% proteins, including oleosins, steroleosins, and caleosins. In this study, a caleosin isoform of ∼30 kDa was identified in the olive pollen grain. The protein was mainly located at the boundaries of the oil bodies in the cytoplasm of the pollen grain and the pollen tube. In addition, caleosins were also visualized in the cytoplasm at the subapical zone, as well as in the tonoplast of vacuoles present in the pollen tube cytoplasm. The cellular behaviour of lipid bodies in the olive pollen was also monitored during in vitro germination. The number of oil bodies decreased 20-fold in the pollen grain during germination, whereas the opposite tendency occurred in the pollen tube, suggesting that oil bodies moved from one to the other. The data suggest that this pollen caleosin might have a role in the mobilization of oil bodies as well as in the reorganization of membrane compartments during pollen in vitro germination

An introduction to geometry through anchored instruction

In this chapter we describe preliminary research on three geometry adventures that are part of the The Adventures of Jasper Woodbury problem-solving series (Cognition and Technology Group at Vanderbilt University [CGTV], 1990).https://scholarlycommons.pacific.edu/ed-facbooks/1027/thumbnail.jp

An introduction to geometry through anchored instruction

In this chapter we describe preliminary research on three geometry adventures that are part of the The Adventures of Jasper Woodbury problem-solving series (Cognition and Technology Group at Vanderbilt University [CGTV], 1990).https://scholarlycommons.pacific.edu/ed-facbooks/1027/thumbnail.jp

The intersection of genetic and chemical genomic screens identifies GSK-3α as a target in human acute myeloid leukemia

Acute myeloid leukemia (AML) is the most common form of acute leukemia in adults. Long-term survival of patients with AML has changed little over the past decade, necessitating the identification and validation of new AML targets. Integration of genomic approaches with small-molecule and genetically based high-throughput screening holds the promise of improved discovery of candidate targets for cancer therapy. Here, we identified a role for glycogen synthase kinase 3α (GSK-3α) in AML by performing 2 independent small-molecule library screens and an shRNA screen for perturbations that induced a differentiation expression signature in AML cells. GSK-3 is a serine-threonine kinase involved in diverse cellular processes, including differentiation, signal transduction, cell cycle regulation, and proliferation. We demonstrated that specific loss of GSK-3α induced differentiation in AML by multiple measurements, including induction of gene expression signatures, morphological changes, and cell surface markers consistent with myeloid maturation. GSK-3α–specific suppression also led to impaired growth and proliferation in vitro, induction of apoptosis, loss of colony formation in methylcellulose, and anti-AML activity in vivo. Although the role of GSK-3β has been well studied in cancer development, these studies support a role for GSK-3α in AML