Retinoic-acid-mediated HRas stabilization induces neuronal differentiation of neural stem cells during brain development.

Ras signaling is tightly regulated during neural stem cell (NSC) differentiation, and defects in this pathway result in aberrant brain development. However, the mechanism regulating Ras signaling during NSC differentiation was unknown. Here, we show that stabilized HRas specifically induces neuronal differentiation of NSCs.

CXXC5 is a transcriptional activator of Flk-1 and mediates bone morphogenic protein-induced endothelial cell differentiation and vessel formation.

CXXC5 is a member of a small subset of proteins containing CXXC-type zinc-finger domain. Here, we show that CXXC5 is a transcription factor activating Flk-1, a receptor for vascular endothelial growth factor. CXXC5 and Flk-1 were accumulated in nucli and membrane of mouse embryonic stem cells (mESCs), respectively, during their endothelial differentiation.

Colon-targeted cell-permeable NFκB inhibitory peptide is orally active against experimental colitis.

For the purpose of development of orally active peptide therapeutics targeting NFκB for treatment of inflammatory bowel disease (IBD), two major barriers in oral delivery of therapeutic peptides, metabolic lability and tissue impermeability, were circumvented by introduction of a colon-targeted delivery system and cell permeable peptides (CPP) to NFκB inhibitory peptides (NIP). Suppression of NFκB activation was compared following treatment with various CPP conjugated NIPs (CPP-NIP). The most potent CPP-NIP was loaded in a capsule coated with a colon specific polymer, which was administered orally to colitic rats.

IL-15 promotes osteoclastogenesis via the PLD pathway in rheumatoid arthritis.

Osteoclastogenesis plays an important role in joint destruction in rheumatoid arthritis (RA). IL-15 is a pleiotropic proinflammatory cytokine that appears to help mediate the pathological bone loss. This study was undertaken to explore the signaling molecules essential for osteoclastogenesis mediated by IL-15 in rheumatoid synovial fibroblasts.

Role of phospholipase D in regulation of testicular Leydig cell hyperplasia in Sprague-Dawley rats treated with di(2-ethylhexyl) phthalate.

This study was conducted to determine the functional role of phospholipase D (PLD) involved in testicular Leydig cell damage caused by di (2-ethylhexyl) phthalate (DEHP) in Sprague-Dawley rats. DEHP (500 mg/kg/day) was administered orally to prepubertal rats for 1, 7, 14, 21 or 28 days. After 7 days of exposure, DEHP produced morphological changes in the testis, including alterations in seminiferous tubule diameters and loss of spermatogenic cells.

Mitochondrial oxidative phosphorylation system is recruited to detergent-resistant lipid rafts during myogenesis.

Since detergent-resistant lipid rafts play important roles in the signal transduction for myogenesis, their comprehensive proteomic analysis could provide new insights to understand their function in myotubes. Here, the detergent-resistant lipid rafts were isolated from C2C12 myotubes and analyzed by capillary RPLC/MS/MS. Among the 327 proteins (or protein groups) identified, 28% were categorized to the plasma membrane or raft proteins, 29% to mitochondria, 20% to microsomal proteins, 10% to other proteins, and 13% to unknown proteins.

Characterization of the surface immobilized synthetic heparin binding domain derived from human fibroblast growth factor-2 and its effect on osteoblast differentiation.

Fibroblast growth factor (FGF)-2 regulates a variety of cellular functions, such as proliferation and differentiation, by binding to cell surface FGF receptors (FGFRs) in the presence of heparin proteoglycans. FGF-2 is known as a heparin-binding growth factor, but the localization of the heparin binding site has not been fully investigated until now. We used two potential heparin binding domains of FGF-2, the residues 105-111 (F105, YKRSRYT) and 119-135 (F119, KRTGQYKLGSKTGPGQK).

Molecular evolution of the periphilin gene in relation to human endogenous retrovirus m element.

HERV-M (human endogenous retrovirus M), related to the super family of HERV-K, has a methionine (M) tRNA primer-binding site, and is located within the periphilin gene on human chromosome 12q12. HERV-M has been integrated into the periphilin gene as the truncated form, 5'LTR-gag-pol-3'LTR. Polymerase chain reaction (PCR) and reverse transcription-polymerase chain reaction (RT-PCR) approaches were conducted to investigate its evolutionary origins.

Fluoxetine blocks cloned neuronal A-type K+ channels Kv1.4.

The effects of fluoxetine were studied on cloned K+ channel Kv1.4 stably expressed in Chinese hamster ovary (CHO) cells using the whole-cell configuration of the patch-clamp technique. Extracellular application of various concentrations of fluoxetine inhibited the amplitude of the peak current of Kv1.