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41	Some aspects of male vervet monkey behaviour Freeman, Natalie J January 2012 (has links) The permanent coresidence of males within a troop is unusual but occurs in vervet monkeys. Several hypotheses have been projected to explain the coexistence of male vervets (predation risk, breeding season length) but these hypotheses fall short in explaining the multimale nature of vervet monkeys. In order to determine the explanation for coresiding males, I collected male behavioural data from two troops over the course of nine months. My dataset was divided into two categories, male-male interactions and female-male interactions. The male-male data indicate that breeding season is the most active time for migration, aggressions and wounds. Coalitions were described for the first time, and affiliative interactions between males highlighted coping tactics of males in regards to their coexistence. The female-male data indicate there was little indication for distinct male or female choice for mating. Specifically, olfactory information appears to lower successful copulations of males, and female resistance also decreased successful copulations. Grooming was not a commodity traded for mating access. Male dominance was not correlated with mating success, and females seem to express their preference for sexual partners. The large cohort of males of my troops appears to alter behaviours observed at other sites. The maintenance of male-female associations after breeding season suggests that males may be preparing for next breeding season, and males may co-reside for breeding purposes. / xiii, 123 leaves : ill. maps ; 29 cm Cohort analysis Dissertations, Academic
42	Contingency and context in the relationships of female vervet monkeys Forshaw, Nicola L January 2011 (has links) This study explored the organizing principles of female sociality in free-ranging vervet monkeys (Chlorocebus aethiops) inhabiting the Klein Karoo, South Africa. Females groomed more than males, grooming peaked at the end of the day and less grooming occurred during the mating season. Although females competed over food, they did not compete over grooming partners, rarely formed coalitions and did not trade grooming against other activities. Instead, they maintained grooming whilst trading between feeding and resting and feeding and moving. Despite seasonal shifts in food competition, grooming was not traded for tolerance and there was an upper limit to cohort size before clique size declined. Inter-population comparisons revealed no troop size effects on clique size, aggression and competition over high-ranking grooming partners. The rarity of coalitions suggests coalitions are unlikely to be a central component of female relationships. / xiii, 162 leaves : ill., maps ; 29 cm Dissertations, Academic
43	Agonist-induced PKC phosphorylation regulates GluK2 SUMOylation and kainate receptor endocytosis Konopacki, F.A., Jaafari, N., Rocca, D.L., Wilkinson, K.A., Chamberlain, S.E., Rubin, P., Kantamneni, Sriharsha, Mellor, J.R., Henley, J.M. January 2011 (has links) No / The surface expression and regulated endocytosis of kainate (KA) receptors (KARs) plays a critical role in neuronal function. PKC can modulate KAR trafficking, but the sites of action and molecular consequences have not been fully characterized. Small ubiquitin-like modifier (SUMO) modification of the KAR subunit GluK2 mediates agonist-evoked internalization, but how KAR activation leads to GluK2 SUMOylation is unclear. Here we show that KA stimulation causes rapid phosphorylation of GluK2 by PKC, and that PKC activation increases GluK2 SUMOylation both in vitro and in neurons. The intracellular C-terminal domain of GluK2 contains two predicted PKC phosphorylation sites, S846 and S868, both of which are phosphorylated in response to KA. Phosphomimetic mutagenesis of S868 increased GluK2 SUMOylation, and mutation of S868 to a nonphosphorylatable alanine prevented KA-induced SUMOylation and endocytosis in neurons. Infusion of SUMO-1 dramatically reduced KAR-mediated currents in HEK293 cells expressing WT GluK2 or nonphosphorylatable S846A mutant, but had no effect on currents mediated by the S868A mutant. These data demonstrate that agonist activation of GluK2 promotes PKC-dependent phosphorylation of S846 and S868, but that only S868 phosphorylation is required to enhance GluK2 SUMOylation and promote endocytosis. Thus, direct phosphorylation by PKC and GluK2 SUMOylation are intimately linked in regulating the surface expression and function of GluK2-containing KARs. Alanine Amino acid substitution Animals Blotting Western COS cells Cercopithecus aethiops Endocytosis HEK293 cells Humans Kainic acid Luminescent proteins Microscopy Mutation Neurons Phosphorylation Protein kinase C Rats Wistar Receptors SUMO-1 Protein Serine Sumoylation REF 2014
44	Dietary flavonoid (-)epicatechin stimulates phosphatidylinositol 3-kinase-dependent anti-oxidant response element activity and up-regulates glutathione in cortical astrocytes Bahia, P.K., Rattray, Marcus, Williams, R.J. 09 1900 (has links) No / Flavonoids are plant-derived polyphenolic compounds with neuroprotective properties. Recent work suggests that, in addition to acting as hydrogen donors, they activate protective signalling pathways. The anti-oxidant response element (ARE) promotes the expression of protective proteins including those required for glutathione synthesis (xCT cystine antiporter, gamma-glutamylcysteine synthetase and glutathione synthase). The use of a luciferase reporter (ARE-luc) assay showed that the dietary flavan-3-ol (-)epicatechin activates this pathway in primary cortical astrocytes but not neurones. We also examined the distribution of NF-E2-related factor-2 (Nrf2), a key transcription factor in ARE-mediated gene expression. We found, using immunocytochemistry, that Nrf2 accumulated in the nuclei of astrocytes following exposure to tert-butylhydroquinone (100 microM) and (-)epicatechin (100 nM). (-)Epicatechin signalling via Nrf2 was inhibited by wortmannin implicating a phosphatidylinositol 3-kinase-dependent pathway. Finally, (-)epicatechin increased glutathione levels in astrocytes consistent with an up-regulation of ARE-mediated gene expression. Together, this suggests that flavonoids may be cytoprotective by increasing anti-oxidant gene expression. Animals Antioxidants Astrocytes COS cells Catechin Cells Cercopithecus aethiops Cerebral cortex Enzyme inhibitors Flavonoids Food Gene expression regulation Glutathione Hydroquinones Mice NF-E2-related factor 2 Neuroprotective agents Oxidative stress Phosphatidylinositol 3-kinases Response elements Signal transduction Up-regulation

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