27 research outputs found

    SHANK3 mutations identified in autism lead to modification of dendritic spine morphology via an actin-dependent mechanism

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    Genetic mutations of SHANK3 have been reported in patients with intellectual disability, autism spectrum disorder (ASD) and schizophrenia. At the synapse, Shank3/ProSAP2 is a scaffolding protein that connects glutamate receptors to the actin cytoskeleton via a chain of intermediary elements. Although genetic studies have repeatedly confirmed the association of SHANK3 mutations with susceptibility to psychiatric disorders, very little is known about the neuronal consequences of these mutations. Here, we report the functional effects of two de novo mutations (STOP and Q321R) and two inherited variations (R12C and R300C) identified in patients with ASD. We show that Shank3 is located at the tip of actin filaments and enhances its polymerization. Shank3 also participates in growth cone motility in developing neurons. The truncating mutation (STOP) strongly affects the development and morphology of dendritic spines, reduces synaptic transmission in mature neurons and also inhibits the effect of Shank3 on growth cone motility. The de novo mutation in the ankyrin domain (Q321R) modifies the roles of Shank3 in spine induction and morphology, and actin accumulation in spines and affects growth cone motility. Finally, the two inherited mutations (R12C and R300C) have intermediate effects on spine density and synaptic transmission. Therefore, although inherited by healthy parents, the functional effects of these mutations strongly suggest that they could represent risk factors for ASD. Altogether, these data provide new insights into the synaptic alterations caused by SHANK3 mutations in humans and provide a robust cellular readout for the development of knowledge-based therapies

    Recent Finance Advances in Information Technology for Inclusive Development: A Survey

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    Reinventing foreign aid for inclusive and sustainable development: a survey

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    This survey essay reviews over 200 papers in arguing that in order to achieve sustainable and inclusive development, foreign aid should not orient developing countries towards industrialisation in the perspective of Kuznets but in the view of Piketty. Abandoning the former’s view that inequality will fall with progress in industrialisation and placing more emphasis on inequality in foreign aid policy will lead to more sustainable development outcomes. Inter alia: mitigate short-term poverty; address concerns of burgeoning population growth; train recipient governments on inclusive development; fight corruption and mismanagement and; avoid the shortfalls of celebrated Kuznets’ conjectures. We discuss how the essay addresses post-2015 development challenges and provide foreign aid policy instruments with which discussed objectives can be achieved. In summary, the essay provides useful policy measures to avoid past pitfalls. ‘Output may be growing, and yet the mass of the people may be becoming poorer’ (Lewis, 1955). ‘Lewis led all developing countries to water, proverbially speaking, some African countries have so far chosen not to drink’ (Amavilah, 2014). Piketty (2014) has led all developing countries to the stream again and a challenging policy syndrome of our time is how foreign aid can help them to drink

    The sedimentology and diagenesis of the Pendleside limestone group in the Craven Basin of Northern England. Available in 2 volumes.

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    This thesis describes the stratigraphy, sedimentology and diagenesis of the Pendleside Limestone (Asbian age), a sequence of limestones, shales and dolostones in the Clitheroe area of N. W. England. Field study of 19 measured sections indicates that it was deposited in a rhythmically subsiding basin (Craven Basin) because of movements on the Mid-Craven Fault which was active in Dinantian times. The sequence is up to 190m thick and consists mostly of distal turbidite deposits which have been reworked at horizons when sediment accumulation built up to the wave base. The original depositional fabric and mineralogy of the Pendleside Limestone Group has been extensively modified by diagenetic processes including cementation, authi­genesis, dolomitization and silicification. These processes have been studied using a wide variety of laboratory techniques. The carbonate cements of the PendIeside Limestone consist predominantly of ferroan calcite and non-ferroan calcite with microdolomite incIusions. The former is probably a stable replacement of original-high-magnesian calcite. Cementation was accompanied by the formation of authigenic albite and quartz. Much of the upper part of the Pendleside Limestone has been extensively dolomitized and chertified. Several distinct zones of dolomitization are found which increase in thickness and intensity towards the top of the Pendleside Limestone Group. The dolostone horizons correspond to coarser-grained lithologies deposited during periods of shallow water sedimentation. The composition of the dolomites changes from ferroan dolomite in the lower part of the Group to non-ferroan dolomite in the upper part. The low strontium and sodium content of the dolostones in association with the other evidence suggests that the dolomitization was brought about in an open system by the mixing of marine and fresh water in phreatic lens which were established at periodic intervals. The dolomitization was closely associated with chertification although this was initiated by the dissolution of siliceous spicules which provided the necessary source of silica

    Authigenic albite in the Pendleside Formation (Dinantian) of northern England

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    SummaryAuthigenic albite occurring as euhedral overgrowths up to 400 μm in size is a characteristic feature of the Pendleside Limestone in the Craven Basin of northern England. The albite is very pure, low-albite in keeping with other authigenic albites in carbonate rocks. The detrital cores of the albites are angular plagioclase grains of approximately An20 composition which are sometimes altered to kaolinite. The albite crystals with their detrital cores are frequently concentrated in discrete laminae, suggesting that the plagioclase cores may have been supplied by a basic volcanogenic source. This view is supported by geochemical studies of limestones which reveal significant correlation between K–Na, Na–Al and K–Al.Interstitial alteration of detrital components, in particular the reaction intermediate plagioclase → kaolinite + albite, was primarily responsible for albite authigenesis. The initial products of this reaction probably included smectite which fixed Mg2+ in the decomposing volcanic grains. Subsequent alteration of the smectite resulted in the formation of small microdolomite inclusions which are commonly seen in the authigenic albites. An equilibrium model in terms of Na+/H4 ratios and H4SiO4 activity is proposed for the silicate assemblages in the Pendleside Formation.</jats:p

    Four of eleven loci required for transient complementation of human cytomegalovirus DNA replication cooperate to activate expression of replication genes

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    As previously shown, 11 loci are required to complement human cytomegalovirus (HCMV) DNA replication in a transient-transfection assay (G. S. Pari and D. G. Anders, J. Virol. 67:6979-6988, 1993). Six of these loci encode known or candidate replication fork proteins, as judged by sequence and biochemical similarities to herpes simplex virus homologs of known function; three encode known immediate early regulatory proteins (UL36-38, IRS1/TRS1, and the major immediate early region spanning UL122-123); and two encode early, nucleus-localized proteins of unknown functions (UL84 and UL112-113). We speculated that proteins of the latter five loci might cooperate to promote and regulate expression of the six replication fork proteins. To test this hypothesis we made luciferase reporter plasmids for each of the replication fork gene promoters and measured their activation by the candidate effectors, expressed under the control of their respective native promoters, using a transient-cooperativity assay in which the candidate effectors were subtracted individually from a transfection mixture containing all five loci. The combination of UL36-38, UL112-113, IRS1, or TRS1 and the major immediate early region produced as much as 100-fold-higher expression than the major immediate early region alone; omitting any one of these four loci from complementing mixtures produced a significant reduction in expression. In contrast, omitting UL84 had insignificant (less than twofold), promoter-dependent effects on reporter activity, and these data do not implicate UL84 in regulating HCMV early-gene expression. Most of the effector interactions showed significant positive cooperativity, producing synergistic enhancement of expression. Similar responses to these effectors were observed for the each of the promoters controlling expression of replication fork proteins. However, subtracting UL112-113 had little if any effect on expression by the UL112-113 promoter or by the simian virus 40 promoter-enhancer under the same conditions. Several lines of evidence argue that the cooperative interactions observed in our transient-transfection assays are important to viral replication in permissive cells. Therefore, the data suggest a model in which coordinate expression of multiple essential replication proteins during permissive infection is vitally dependent upon the cooperative regulatory interactions of proteins encoded by multiple loci and thus have broad implications for our understanding of HCMV biology.</jats:p

    Multiple regulatory events influence human cytomegalovirus DNA polymerase (UL54) expression during viral infection

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    The human cytomegalovirus (HCMV) DNA polymerase gene (UL54; also called pol) is a prototypical early gene in that expression is mandatory for viral DNA replication. Recently, we have identified the major regulatory element in the UL54 promoter responsive to the major immediate early (MIE) proteins (UL122 and UL123) (J.A. Kerry, M.A. Priddy, and R. M. Stenberg, J. Virol. 68:4167-4176, 1994). Mutation of this element, inverted repeat sequence 1 (IR1), abrogates binding of cellular proteins to the UL54 promoter and reduces promoter activity in response to viral proteins in transient-transfection assays. To extend our studies on the UL54 promoter, we aimed to examine the role of IR1 in UL54 regulation throughout the course of infection. These studies show that viral proteins in addition to the MIE proteins can activate the UL54 promoter. Proteins from UL112-113 and IRS1/TRS1, recently identified as essential loci for transient complementation of HCMV oriLyt-dependent DNA replication, were found to function as transactivators of the UL54 promoter in association with MIE proteins. UL112-113 enhanced UL54 promoter activation by MIE proteins three- to fourfold. Constitutive expression of UL112-113 demonstrated that the MIE protein dependence of UL112-113 transactivational activity was not related to activation of cognate promoter sequences, suggesting that UL112-113 proteins function in cooperation with the MIE proteins. Mutation of IR1 was found to abrogate stimulation of the UL54 promoter by UL112-113, suggesting that this element is also involved in UL112-113 stimulatory activity. These results demonstrate that additional viral proteins influence UL54 promoter expression in transient-transfection assays via the IR1 element. To confirm the biological relevance of IR1 in regulating UL54 promoter activity during viral infection, a recombinant virus construct containing the UL54 promoter with a mutated IR1 element regulating expression of the chloramphenicol acetyltransferase (CAT) reporter gene (RVIRmCAT) was generated. Analysis of RVIRmCAT revealed that mutation of IR1 dramatically reduces UL54 promoter activity at early times after infection. However, at late times after infection CAT expression by RVIRmCAT, as assessed by RNA and protein levels, was approximately equivalent to expression by wild-type RVpolCAT. These data demonstrate IR1-independent regulation of the UL54 promoter at late times after infection. Together these results show that multiple regulatory events affect UL54 promoter expression during the course of infection.</jats:p
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