BACKGROUND Colony-stimulating factor-1 (CSF-1), a growth and survival factor for osteoclasts, stimulates these cells to spread and migrate towards a gradient of CSF-1. This may support the translocation of osteoclasts to new sites on the bone surface to be resorbed. Phosphoinositide 3-kinase (PI 3-K) is a lipid kinase participating in various signal transduction pathways. OBJECTIVE To investi...

On a regular tetrahedron in spherical space there exist the finite number of simple closed geodesics. For any pair coprime integers $(p,q)$ it was found numbers $\alpha_1$ and $\alpha_2$ depending on $p$, $q$ satisfying inequalities $\pi/3< \alpha_1 < \alpha_2 2\pi/3$ such that with faces angle $\alpha \in \left( \pi/3, \right)$ exists unique, up to rigid motion tetrahedron, geodesic type $(p,q...

Previously we have shown that PDGF receptor mutants that do not bind PI-3 kinase internalize after ligand binding, but fail to downregulate and degrade. To define further the role of PI-3 kinase in trafficking processes in mammalian cells, we have investigated the effects of a potent inhibitor of PI-3 kinase activity, wortmannin. At nanomolar concentrations, wortmannin inhibited both the transf...

It has been shown that inhibition of phosphatidylinositol (PI) 3-kinase blocks neurite outgrowth of PC12 cells stimulated with nerve growth factor. To further assess the role of PI 3-kinase, the active form of PI 3-kinase was expressed in PC12 cells by the adenovirus mediated introduction of a site-specific recombinase, Cre. After expression of the active PI 3-kinase, elevation of the levels of...

In canine colon, M2/M3 muscarinic receptors are coupled to extracellular signal-regulated kinase (ERK) and p38 mitogen-activated protein (MAP) kinases. We tested the hypothesis that this coupling is mediated by enzymes of the phosphatidylinositol (PI) 3-kinase family. RT-PCR and Western blotting demonstrated expression of two isoforms, PI 3-kinase-alpha and PI 3-kinase-gamma. Muscarinic stimula...

The activation status of the guanosine triphosphate (GTP)-binding protein Ras is dictated by the relative intensities of two opposing reactions: the formation of active Ras-GTP complexes, promoted by guanine-nucleotide exchange factors (GEFs), and their conversion to inactive Ras-GDP as a result of the deactivating action of GTPase-activating proteins (GAPs). The relevance of phosphoinositide 3...

The radially excited pseudoscalar state $\eta(1295)$ is still poorly understood [as well as its $SU(3)$ partners $\pi(1300)$ and $K(1460 )$] we want to attract attention experimenters comprehensive study. As for the main three-body decay $\eta(1295)\to \eta\pi\pi$, here interest measurements of shapes $\eta\pi $ $\pi\pi$ mass spectra in which contributions from $a_0(980)$ resonance large $S$ wa...

Generation and turnover of phosphoinositides (PIs) must be coordinated in a spatial- and temporal-restricted manner. The small GTPase Rab5 interacts with two PI 3-kinases, Vps34 and PI3Kbeta, suggesting that it regulates the production of 3-PIs at various stages of the early endocytic pathway. Here, we discovered that Rab5 also interacts directly with PI 5- and PI 4-phosphatases and stimulates ...

The Rockefeller University Press $30.00 J. Cell Biol. Vol. 185 No. 5 917–928 www.jcb.org/cgi/doi/10.1083/jcb.200903020 JCB 917 Correspondence to Sergio Grinstein: [email protected] Abbreviations used in this paper: FRET, fluorescence resonance energy transfer; LUV, large unilamellar vesicle; mRFP, monomeric RFP; PA, phosphatidic acid; PC, phosphatidylcholine; PE, phosphatidylethanolamine; PI, pho...