Gene up-regulation by DNA demethylation in 35S-gshI-transgenic poplars (Populus x canescens)

Gene expression levels of transgene 35S-gshI (γ-glutamylcysteine synthetase) cloned from E. coli, and the endogenous gene gsh1 of poplar (Populus x canescens) were upregulated by the DNA demethylating agent DHAC (5,6-dihydro-5'-azacytidine hydrochloride) (10-4 M for 7 days) in aseptic leaf discs cultures. Two 35S-gshI-transgenic (6lgl and 11ggs) and wild type (WT) poplar clones were used. The efficiency of gene upregulation was also analyzed under herbicide paraquat stress (4 x 10-7 M). Levels of gshI-mRNA and gsh1-mRNA were determined by RT-qPCR (reverse transcriptase quantitative PCR) after cDNA synthesis. For internal control, the constitutively expressed housekeeping poplar genes α-tubulin and actin were used, and the 2−HHCt method was applied for data analysis. In long term DHAC treatment (21 days), a morphogenetic response of de novo root development was observed on leaf discs in a wide concentration range of DHAC (10-8 to 10-6 M). Adventitious shoots (11ggs clone) also emerged from leaf discs after a combined treatment with DHAC (10-4 M) and paraquat (10-7 M). Shoots were dissected, rooted and transplanted in glass houses for further analyses for phytoremediation capacity. Since DNA methylation patterns are inherited (epigenetic memory), these poplar plants with increased gene expression levels of both transgene 35S-gshI and endogenous gene gsh1 provide novel plant sources for in situ application

Feketenyár (Populus nigra) gametoklónok mikroszatellita változatossága; (TTCTGG)5 deléció a WPMS-20 lokuszon.

A nyárfajok (Populus ssp) extrém kis méretű genomja (2n=4×=38; 5.5×108 bp; 2C=1.1 pg) nagyfokú genetikai stabilitással párosul. Munkánk célja a feketenyár (Populus nigra) genetikai variabilitásának növelése volt haploid (n) indukció alkalmazásával, portoktenyészetben, két portok-donor klón (N-SL és N-309) alkalmazásával. A felnevelt haploid utódok (1-35) genetikai polimorfizmus elemzését öt SSR lokusz allél diverzitásával jellemeztük. Összesen 20 SSR allél 280 szekvenciáját azonosítottuk, egy-egy lókuszon 1-6 allélgyakorisággal: WPMS-02 (5 allél), WPMS-04 (6 allél), WPMS-06 (2 allél), WPMS-20 (6 allél) és PTR-04 (1 allél). Az elemzést ALF (automatic laser fluorometer) módszerrel végeztük. A WPMS-20 allél szekvencia elemzésével egy 5-szörös (TTCTGG) deléciót mutattunk ki a (TTCTGG)8 lokuszon. Az SSR allélek léte, illetve nemléte alapján dendrogramot készítettünk, amely alapján elemeztük és meghatároztuk az új nemesítésű klónok genetikai diverzitását. Az új SSR-klóntípusok jelentős nemesítési alapanyagot szolgáltatnak a nyárfanemesítés számára

Metilviologén (paraquat) toleráns nyárfaklónok (Populus x canescens) szelekciója és alkalmazása fitoremediációban

Paraquat (syn.: metilviologén) toleráns nyárfa (Populus x canescens) klónok szelekcióját végeztük el in vitro kultúrában. A szintetikus talaj összetétele: WPM (Woody Plant Media) tápsók, 1% szacharóz, 0,8 % agar 1 mg/l benziladenin, 0,2 mg/l naftilecetsav és paraquat koncentráció sor (2×10(-6) M, 1,47×10(-6) M, 9,3×10(-7) M, 4×10(-7) M) volt. A regeneránsokat szelekciós táptalajon történő tesztelés után felszaporítottuk (mikroszaporítás), gyökeresítettük, majd üvegházban felneveltük. A molekuláris (RTqPCR) és biokémiai elemzések (aszkorbát peroxidáz, glutation peroxidáz, glutation Stranszferáz, lipoxigenáz) igazolták egy rendkívül stabil paraquat toleráns klón sikeres szelekcióját. A klónokat az in vitro vizsgálatokat követően in situ (Fűzfőgyártelep) teszteljük gyomirtószer maradványok toleranciájára. | Paraquat (syn.: methylviologen) tolerant poplar (P. x canescens) clones (PQT) were selected in in vitro cultures at concentration series of paraquat (2×10(-6) M, 1.47×10(-6) M, 9.3×10(-7) M, 4×10(-7) M). After testing on tissue culture media, regenerants were micropropagated. After rooting, PQT-clones were transplanted to a greenhouse. PQT clones showed significantly higher gst gene expression then wild type (WT) analyzed by RT-qPCR (quantitative reverse transcriptase PCR). For functional analysis enzyme activities of GST (glutathione S-transferase), APOX (ascorbate peroxides), GR (glutathione reductase), and LOX (lipoxygenase, pH 8.0) were determined. After rooting, PQT-clones were transplanted in glass houses, followed by field performance analyses for phytoremediation (environmental clean up using plants) capacity in heavily contaminated area at Balatonfűzfő, Hungar

A gst gén DNS-demetilált overexpressziója a szürkenyár (Populus x canescens) fitoremediációs kapacitásának növelésére

A szürkenyár (Populus x canescens) gst (glutation S-transzferáz) génexpresszióját növeltük meg DHAC-indukált (5,6-dihidro-5'-azacitidin hidroklorid) DNSdemetilációval. Három klónt vizsgáltunk, a természetes (WT) és két glutationtúltermelő 35S-gshI nyárfaklónt (11ggs, 6lgl) RT-qPCR elemzésben. A gst gén megemelt expressziós szintje a DHAC-kezelt kontroll növényekben 4,9-szeresre emelkedett, amely tovább nőtt paraquat stresszben (11,2-szeres), amely eredmény azt bizonyítja, hogy a DNS demetilációjával az endogén gének expressziós szintje nagyságrendekkel emelhető meg. Ismert, hogy a DNS demetiláció a vegetativ klónokban öröklődik (epigenetikus memória), ezért a demetilációs eljárás (gén upreguláció) új lehetőséget ad stressztűrő nyárfaklónok előállítására. | In the study presented gst (glutathione S-transferase) gene expression levels of poplar (Populus x canescens) were analyzed in response to the DNA demethylating agent DHAC (5,6-dihydro-5'-azacytidine hydrochloride). Aseptic leaf discs cultures of wild type (WT) and two gshI-transgenic clones (6lgl and 11ggs) clones were analyzed by RT-qPCR. High expression levels of DHAC treated control plants (4.9-fold increment, and a further 11.2-fold increment after paraquat treatment) proves that DNA demethylation provides powerful tools in gene-upregulation. As DNA methylation patterns are inherited (‘epigenetic memory’) novel poplar plant sources are provided with increased gst gene expression levels

THE ROLE OF KNOWLEDGE AND TECHNOLOGY IN FOOD SAFETY AT SCHOOL CATERING SERVICES IN HUNGARY

Providing the population with safe and good quality food is one of the most important objectives of every country. The outbreak and spread of foodborne diseases is independent of a country’s location or development level, and may occur everywhere. As most children spend their days at educational institutions, we shall focus on their food safety. Not only for their present state of health, but also because childhood nutrition and diet will basically determine their health in their adulthood and thus, influence the future economic and social performance of their society. This paper introduces background information about school catering in Hungary, based upon the results of an overall food safety survey. The results of our research showed that the food safety level of the different kitchen units is mostly determined by the level of food processing activities. The technical and technological level of the school kitchens did not significantly influence the food safety level of the kitchens. According to the results of our survey, improving the knowledge and the attitudes of employees in school kitchens is more important than technical and technological conditions

Enhanced inducibility of glutathione S-transferase activity by paraquat in poplar leaf discs in the presence of sucrose

Leaf discs of the wildtype poplar hybrid Populus canescens and its two transgenic lines overexpressing gamma-glutamylcysteine synthetase in the cytosol or in the chloroplasts were exposed to the herbicide paraquat (4 x 10(-9) to 4 x 10(-6) M). Leaf discs were incubated on tissue culture media containing 0.2, 1.0 or 2.0% sucrose. Exposure to paraquat led to a concentration-dependent decrease of GST activities at 0.2% sucrose. However, at higher external sucrose supplies, paraquat brought about marked inductions of GST activities in all poplar lines. The GST induction was light-dependent. Fluorescence measurements showed that the efficiency of the photosynthetic apparatus was inhibited by high paraquat concentrations (4 x 10(-7) - 4 x 10(-6) M) in all poplar clones. The photosynthetic efficiency (F-v/F-m) decreased also in leaf discs incubated in continuous darkness in the presence of paraquat

The vegetable production programme

The authors' collective when drawing up the development of the vegetable branch emphasizes the supposition that in the future the domestic products will be overwhelming on the home market, a significant quantity of commodities will be exported into neighbouring countries, we may be continuously present at the EU market. All these conditions can be based only on strong state assistance

The vegetable production programme

The authors' collective when drawing up the development of the vegetable branch emphasizes the supposition that in the future the domestic products will be overwhelming on the home market, a significant quantity of commodities will be exported into neighbouring countries, we may be continuously present at the EU market. All these conditions can be based only on strong state assistance