Millipore Sigma Vibrant Logo
 

ipvh00010


40 Results Advanced Search  
Showing
Products (2)
Documents (38)
Site Content (0)

Narrow Your Results Use the filters below to refine your search

Document Type

  • (28)
  • (4)
  • (2)
  • (2)
  • (1)
  • Show More
Can't Find What You're Looking For?
Contact Customer Service

 

  • Biochemical and functional properties of distinct nicotinic acetylcholine receptors in the superior cervical ganglion of mice with targeted deletions of nAChR subunit gen ... 20377613

    Nicotinic acetylcholine receptors (nAChRs) mediate fast synaptic transmission in ganglia of the autonomic nervous system. Here, we determined the subunit composition of hetero-pentameric nAChRs in the mouse superior cervical ganglion (SCG), the function of distinct receptors (obtained by deletions of nAChR subunit genes) and mechanisms at the level of nAChRs that might compensate for the loss of subunits. As shown by immunoprecipitation and Western blots, wild-type (WT) mice expressed: alpha 3 beta 4 (55%), alpha 3 beta 4 alpha 5 (24%) and alpha 3 beta 4 beta 2 (21%) nAChRs. nAChRs in beta 4 knockout (KO) mice were reduced to < 15% of controls and no longer contained the alpha 5 subunit. Compound action potentials, recorded from the postganglionic (internal carotid) nerve and induced by preganglionic nerve stimulation, did not differ between alpha 5 beta 4 KO and WT mice, suggesting that the reduced number of receptors in the KO mice did not impair transganglionic transmission. Deletions of alpha 5 or beta2 did not affect the overall number of receptors and we found no evidence that the two subunits substitute for each other. In addition, dual KOs allowed us to study the functional properties of distinct alpha 3 beta4 and alpha 3 beta 2 receptors that have previously only been investigated in heterologous expression systems. The two receptors strikingly differed in the decay of macroscopic currents, the efficacy of cytisine, and their responses to the alpha-conotoxins AuIB and MII. Our data, based on biochemical and functional experiments and several mouse KO models, clarify and significantly extend previous observations on the function of nAChRs in heterologous systems and the SCG.
    Document Type:
    Reference
    Product Catalog Number:
    Multiple
    Product Catalog Name:
    Multiple

  • Parp1 facilitates alternative NHEJ, whereas Parp2 suppresses IgH/c-myc translocations during immunoglobulin class switch recombination. 19364882

    Immunoglobulin class switch recombination (CSR) is initiated by DNA breaks triggered by activation-induced cytidine deaminase (AID). These breaks activate DNA damage response proteins to promote appropriate repair and long-range recombination. Aberrant processing of these breaks, however, results in decreased CSR and/or increased frequency of illegitimate recombination between the immunoglobulin heavy chain locus and oncogenes like c-myc. Here, we have examined the contribution of the DNA damage sensors Parp1 and Parp2 in the resolution of AID-induced DNA breaks during CSR. We find that although Parp enzymatic activity is induced in an AID-dependent manner during CSR, neither Parp1 nor Parp2 are required for CSR. We find however, that Parp1 favors repair of switch regions through a microhomology-mediated pathway and that Parp2 actively suppresses IgH/c-myc translocations. Thus, we define Parp1 as facilitating alternative end-joining and Parp2 as a novel translocation suppressor during CSR.
    Document Type:
    Reference
    Product Catalog Number:
    IPVH00010
    Product Catalog Name:
    Immobilon®-P PVDF Membrane

  • Effects of HIV protease inhibitors on progression of monocrotaline- and hypoxia-induced pulmonary hypertension in rats. 20974998

    Pulmonary hypertension (PH) is among the complications of HIV infection. Combination antiretroviral therapy may influence the progression of HIV-related PH. Because Akt signaling is a potential molecular target of HIV protease inhibitors (HPIs), we hypothesized that these drugs altered monocrotaline- and hypoxia-induced PH in rats by downregulating the Akt pathway, thereby inhibiting pulmonary artery smooth muscle cell proliferation.
    Document Type:
    Reference
    Product Catalog Number:
    IPVH00010
    Product Catalog Name:
    Immobilon®-P PVDF Membrane

  • Remodeling of VE-cadherin junctions by the human herpes virus 8 G-protein coupled receptor. 20818438

    Kaposi Sarcoma (KS) are opportunistic tumors, associated with human herpes virus 8 (HHV8) infection. KS development is highly favored by immune-depression and remains the second most frequent tumor in acquired immune deficiency syndrome patients. Although it has been shown that experimental expression of the HHV8 G-protein-coupled receptor (vGPCR) in the endothelial compartment is alone sufficient to recapitulate the formation and progression of KS-like lesions, its functional effects on endothelial homeostasis are not fully understood. Here we show that vGPCR expression in endothelial cells induces an increase in paracellular permeability both in vivo and in vitro. By using pharmacological inhibitors and small interference RNA-based knockdown, we demonstrate an essential role for the PI(3)Kinase-γ/Rac nexus in vGPCR-mediated permeability. This was further accompanied by dramatic remodeling of VE-cadherin-dependent cell-cell junctions. Importantly, this in vitro vGPCR-initiated signaling signature was observed in a large panel of human KS. Altogether, our results support the hypothesis that endothelial vGPCR signaling is co-opted in KS, and unveil new key cellular targets for therapeutic intervention.
    Document Type:
    Reference
    Product Catalog Number:
    IPVH00010
    Product Catalog Name:
    Immobilon®-P PVDF Membrane

  • Interactions between Brucella suis VirB8 and its homolog TraJ from the plasmid pSB102 underline the dynamic nature of type IV secretion systems. 19251859

    The proteinVirB8 plays a critical role in the assembly and function of the Agrobacterium tumefaciens virB type IV secretion system (T4SS). The structure of the periplasmic domain of both A. tumefaciens and Brucella suis VirB8 has been determined, and site-directed mutagenesis has revealed amino acids involved in the dimerization of VirB8 and interactions with VirB4 and VirB10. We have shown previously that TraJ, the VirB8 homologue from pSB102, and the chimeric protein TraJB8, encompassing the cytoplasmic and transmembrane (TM) domains of TraJ and the periplasmic domain of VirB8, were unable to complement a B. suis mutant containing an in-frame deletion of the virB8 gene. This suggested that the presence of the TraJ cytoplasmic and TM domains could block VirB8 dimerization or assembly in the inner membrane. By bacterial two-hybrid analysis, we found that VirB8, TraJ, and the chimeras can all interact to form both homo- and heterodimers. However, the presence of the TM domain of TraJ resulted in much stronger interactions in both the homo- and heterodimers. We expressed the wild-type and chimeric proteins in wild-type B. suis. The presence of proteins carrying the TM domain of TraJ had a dominant negative effect, leading to complete loss of virulence. This suggests that the T4SS is a dynamic structure and that strong interactions block the spatial flexibility required for correct assembly and function.
    Document Type:
    Reference
    Product Catalog Number:
    IPVH00010
    Product Catalog Name:
    Immobilon®-P PVDF Membrane