This implies that normally much of wt F is not associated with wt HN, in conflict with the clamp model for activation. Correspondingly, we show that wt PIV5 fusion occurs in an HN concentration-dependent manner. Also inconsistent with the clamp model are the findings that BiFC F does not adopt a postfusion conformation when expressed in the absence of HN and that HN coexpression does not
provide resistance to the heat-induced triggering of F. In support of a provocateur model of F activation, CH5183284 concentration we demonstrate by analysis of the morphology of soluble F trimers that the hyperfusogenic mutation S443P has a destabilizing effect on F.”
“The use of the club drugs 3.4-methylenedioxymethamphetamine (MDMA) and 5-methoxy-n,n-diisopropyl-tryptamine (Foxy) is of growing concern, especially as many of the effects, particularly during development, are unknown. The effects of these drugs upon homeostasis may be important since both are known to stimulate the hypothalamic-pituitary-adrenal axis. The purpose of this experiment was to examine alterations in rats in corticosterone and glucose following an
acute exposure to these drugs at different stages of development: preweaning, juvenile, and adulthood. Both MDMA and Foxy increased corticosterone levels significantly at all ages examined, while glucose was elevated at all stages except at the juvenile time point (postnatal day 28). For both measures, there were no differences between the sexes with either drug. The data indicate that an acute exposure to these drugs alters CURT and glucose click here levels, raising the possibility that these changes may have effects on behavioral and cognitive function, as we and others have previously demonstrated. (C) 2009
Elsevier Inc. All rights reserved.”
“As obligatory parasites, viruses co-opt a variety of cellular functions for robust replication. The expression of the nonsegmented negative-strand RNA genome of respiratory syncytial virus (RSV), a significant pediatric pathogen, absolutely requires actin and is stimulated by the actin-regulatory protein profilin. As actin is a major contractile protein, it was important to determine whether the known functional domains of actin and profilin were important for their ability to activate RSV transcription. Analyses of recombinant mutants in a reconstituted SDHB RSV transcription system suggested that the divalent-cation-binding domain of actin is critically needed for binding to the RSV genome template and for the activation of viral RNA synthesis. In contrast, the nucleotide-binding domain and the N-terminal acidic domain were needed neither for template binding nor for transcription. Specific surface residues of actin, required for actin-actin contact during filamentation, were also nonessential for viral transcription. Unlike actin, profilin did not directly bind to the viral template but was recruited by actin.