5′ flanking region of var genes nucleate histone modification patterns linked to phenotypic inheritance of virulence traits in malaria parasites

In the human malaria parasite Plasmodium falciparum antigenic variation facilitates long-term chronic infection of the host. This is achieved by sequential expression of a single member of the 60-member var family. Here we show that the 5′ flanking region nucleates epigenetic events strongly linked to the maintenance of mono-allelic var gene expression pattern during parasite proliferation. Tri- and dimethylation of histone H3 lysine 4 peak in the 5′ upstream region of transcribed var and during the poised state (non-transcribed phase of var genes during the 48 h asexual life cycle), ‘bookmarking’ this member for re-activation at the onset of the next cycle. Histone H3 lysine 9 trimethylation acts as an antagonist to lysine 4 methylation to establish stably silent var gene states along the 5′ flanking and coding region. Furthermore, we show that competition exists between H3K9 methylation and H3K9 acetylation in the 5′ flanking region and that these marks contribute epigenetically to repressing or activating var gene expression. Our work points to a pivotal role of the histone methyl mark writing and reading machinery in the phenotypic inheritance of virulence traits in the malaria parasite

Natural-geographic characteristics of Bjelovar-bilogora County in the function of tourism development

Bjelovarsko-bilogorska županija smještena je u Središnjoj hrvatskoj zavali te ima povoljne prirodnogeografske uvjete za razvoj turizma. Županija ima dobar geoprometni položaj prema najvećoj urbanoj aglomeraciji koja je ujedno i najveće turističko središte kontinentalne Hrvatske. Usprkos bogatoj i raznolikoj prirodnogeografskoj samo je zdravstveno-lječilišni turizam sustavno razvijan od druge polovice 20. stoljeća, a sve veća važnost pridaje se lovnom i ruralnom turizmu. Za potrebe istraživanja provedeno je kvantitativno anketno istraživanje na neprobabilistički odabranom, prigodnom uzorku koji čine građani Republike Hrvatske sa stalnim prebivalištem na području Bjelovarsko-bilogorske županije i oni koji nemaju stalno prebivalište na području Bjelovarsko-bilogorske županije. Na temelju rezultata ankete i analize statističkih podataka utvrđeno je da su posjetitelji uglavnom zadovoljni cjelokupnom turističkom ponudom, no nedostaje im više manifestacija i zabavnih sadržaja. Budući razvoj turizma Bjelovarsko-bilogorske županije trebao bi se temeljiti na nadopuni postojeće turističke ponude koja ima brojne neiskorištene prirodne potencijale, te što boljom promocijom istih.Bjelovar-bilogora County is located in central Croatian basin and has favourable natural-geographical conditions for the tourism development. County has a good geographic position towards the largest urban agglomeration in Croatia, which is also the largest source of domestic travel demand. Despite its rich and diverse natural resource basis, only medical and health tourism has been systematically developed, while the increasing importance is given to hunting and rural tourism. For the purpose of this study quantitative survey on a nonprobabilistic sample consisting of Croatian citizens who have permanent residence in the area of Bjelovar County and others who have not, was conducted. Visitors are mostly satisfied with the overall tourist offer, but they have expressed a desire for a larger number of cultural and entertainment events. Further development of tourism in Bjelovar-bilogora County should be based on the upgrading and better promotion of the existing touristic offer that has many unexploited natural resources

5′ flanking region of genes nucleate histone modification patterns linked to phenotypic inheritance of virulence traits in malaria parasites-3

<p><b>Copyright information:</b></p><p>Taken from "5′ flanking region of genes nucleate histone modification patterns linked to phenotypic inheritance of virulence traits in malaria parasites"</p><p></p><p>Molecular Microbiology 2007;66(6):1296-1305.</p><p>Published online 19 Nov 2007</p><p>PMCID:PMC2228885.</p><p>© 2007 The Authors Journal compilation © 2007 Blackwell Publishing Ltd</p