Knockdown of zif268 in the posterior dorsolateral striatum does not enduringly disrupt a response memory of a rewarded T-maze task

Under certain conditions pavlovian memories undergo reconsolidation, whereby the reactivated memory can be disrupted by manipulations such as knockdown of zif268. For instrumental memories, reconsolidation disruption is less well established. Our previous, preliminary data identified that there was an increase in Zif268 in the posterior dorsolateral striatum (pDLS) after expression of an instrumental habit-like ‘response’ memory, but not an instrumental goal-directed ‘place’ memory on a T-maze task. Here, the requirement for Zif268 in the reconsolidation of a response memory was tested by knockdown of Zif268, using antisense oligodeoxynucleotide infusion into the pDLS, at memory reactivation. Zif268 knockdown reduced response memory expression 72H, but not 7d later. Western blotting revealed a non-significant increase in Zif268 in the pDLS in rats using response memories, but there was no change in Zif268 expression in the hippocampus following retrieval of a place memory. Zif268 expression increased in the basolateral amygdala after memory reactivation whether a response or place strategy was used during reactivation. We propose that Zif268 expression in the basolateral amygdala may be linked to prediction error, generated by the absence of reward at reactivation. Taken together, these results suggest a complex role for Zif268 in the maintenance of instrumental memories.This work was conducted within the Behavioural and Clinical Neuroscience Institute (BCNI), a joint initiative funded by the Wellcome Trust and the UK Medical Research Council, in the Department of Psychology at the University of Cambridge. This work was funded by a UK Medical Research Council programme grant (no. G1002231) awarded to B.J.E. and A.L.M. G.H.V. was supported by a doctoral training grant from the BCNI. A.L.M. is the Ferreras-Willetts Fellow in Neuroscience at Downing College, Cambridge. E.N.C is a BBSRC Anniversary Future Leaders Fellow

Kicking against the PRCs - a domesticated transposase antagonises silencing mediated by polycomb group proteins and is an accessory component of polycomb repressive complex 2

The Polycomb group (PcG) and trithorax group (trxG) genes play crucial roles in development by regulating expression of homeotic and other genes controlling cell fate. Both groups catalyse modifications of chromatin, particularly histone methylation, leading to epigenetic changes that affect gene activity. The trxG antagonizes the function of PcG genes by activating PcG target genes, and consequently trxG mutants suppress PcG mutant phenotypes. We previously identified the ANTAGONIST OF LIKE HETEROCHROMATIN PROTEIN1 (ALP1) gene as a genetic suppressor of mutants in the Arabidopsis PcG gene LIKE HETEROCHROMATIN PROTEIN1 (LHP1). Here, we show that ALP1 interacts genetically with several other PcG and trxG components and that it antagonizes PcG silencing. Transcriptional profiling reveals that when PcG activity is compromised numerous target genes are hyper-activated in seedlings and that in most cases this requires ALP1. Furthermore, when PcG activity is present ALP1 is needed for full activation of several floral homeotic genes that are repressed by the PcG. Strikingly, ALP1 does not encode a known chromatin protein but rather a protein related to PIF/Harbinger class transposases. Phylogenetic analysis indicates that ALP1 is broadly conserved in land plants and likely lost transposase activity and acquired a novel function during angiosperm evolution. Consistent with this, immunoprecipitation and mass spectrometry (IP-MS) show that ALP1 associates, in vivo, with core components of POLYCOMB REPRESSIVE COMPLEX 2 (PRC2), a widely conserved PcG protein complex which functions as a H3K27me3 histone methyltransferase. Furthermore, in reciprocal pulldowns using the histone methyltransferase CURLY LEAF (CLF), we identify not only ALP1 and the core PRC2 components but also plant-specific accessory components including EMBRYONIC FLOWER 1 (EMF1), a transcriptional repressor previously associated with PRC1-like complexes. Taken together our data suggest that ALP1 inhibits PcG silencing by blocking the interaction of the core PRC2 with accessory components that promote its HMTase activity or its role in inhibiting transcription. ALP1 is the first example of a domesticated transposase acquiring a novel function as a PcG component. The antagonistic interaction of a modified transposase with the PcG machinery is novel and may have arisen as a means for the cognate transposon to evade host surveillance or for the host to exploit features of the transposition machinery beneficial for epigenetic regulation of gene activity.Fil: Liang, Shih Chieh. University of Edinburgh; Reino UnidoFil: Hartwig, Ben. Max Planck Institute for Plant Breeding Research; AlemaniaFil: Perera, Pumi. University of Edinburgh; Reino UnidoFil: Mora Garcia, Santiago. Fundación Instituto Leloir; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Bioquimicas de Buenos Aires; ArgentinaFil: de Leau, Erica. University of Edinburgh; Reino UnidoFil: Thornton, Harry. University of Edinburgh; Reino UnidoFil: Lima de Alves, Flavia. University of Edinburgh; Reino UnidoFil: Rapsilber, Juri. University of Edinburgh; Reino UnidoFil: Yang, Suxin. University of Edinburgh; Reino UnidoFil: James, Geo Velikkakam. Max Planck Institute for Plant Breeding Research; AlemaniaFil: Schneeberger, Korbinian. Max Planck Institute for Plant Breeding Research; AlemaniaFil: Finnegan, E. Jean. University of Edinburgh; Reino UnidoFil: Turck, Franziska. Max Planck Institute for Plant Breeding Research; AlemaniaFil: Goodrich, Justin. Mc Gill University; Canad

A survey on the involvement of accident and emergency doctors in medicolegal work in Hong Kong

This study reports the results from a questionnaire survey on the pattern of medico-legal work undertaken by doctors working in Accident & Emergency Departments (ED) and their self-evaluation of competency in forensic medicine. A total of 155 questionnaires were returned with a response rate of 46%. Only 30% (46) respondents were fellows of the Hong Kong College of Emergency Medicine but 46% (71) had more than 6 years of experience working in the ED. Most of the requests for medical report came from police and insurance companies. Fellows had more experience writing reports on homicide, sexual assault and child abuse than non-fellows did. Nearly all fellows and three quarters (74%) of non-fellows had given evidence in courts of law. Physical assault was the commonest and sexual assault the least common experience. Most respondents had experience of attending district court (83%), followed by coroner inquest (67%), magistracy (66%) and high court (45%). Respondents were asked to rate themselves on their competence in various subject areas. It can be seen that respondents were less comfortable in areas like homicide, child abuse and sexual assault. On the job coaching by a senior seems to be the major mode of training. Both fellows (61%) and non-fellows (36%) favored some form of courses with a hands-on workshop element in future. © 2003 Elsevier Ltd and AFP. All rights reserved.link_to_subscribed_fulltex

Exploring the nexus between tourism, remittances and growth in Kenya

Recently there has been a surge in remittances inflow to Kenya while tourism receipts appears to be declining, albeit gradually. In light of these developments, the paper explores the plausible effects of tourism and remittances on per worker output. We use the annual data over 1978–2010 periods and the ARDL bounds approach within the augmented (Solow in Q J Econ 70:65–94, 1956) framework. The regression results show that tourism has a marginal net negative effect in the short-run however positive effect in the long-run. Remittances, on the other hand, have a net positive effect in short-run and negative effect in the long-run. The key results from the Toda–Yamamoto Granger non-causality (Toda and Yamamoto in J Econom 66:225–250, 1995) results show a unidirectional causation from remittances to output per worker; and from output per worker to tourism. A unidirectional ‘combined effect’ of all variables causing output and remittances, respectively are evident as well. Conclusively, tourism is one of the leading drivers of Kenyan economy. To boost gains from tourism, the sector needs to align policies to the Kenya 2030 strategic framework with significant focus on expanding markets, boosting investment, and growth. Remittances market need to be further developed strategically with the view to improving Kenyan migrant led growth initiatives with plausible links to tourism development