Defining the corrosion surface of the dolines by means of a digital elevation model

The complex study of most typical karst features, the dolines, forms an important part of karst morphological research. The varied surface of the karst, the individual shapes of the dolines can only be analysed with the help of proper cartographical methods and a holistic approach. The use of dipital elevation models provides pssibility to compőute the precise slope values and trough these to specify the real area values of the surface (as opposed to the area in projection)

Data for the geoecology of solution karst dolines, with particular attention to climatic, soil and biogenic environment

The appearance and spatial distribution of the solution dolines of the temperate karsts are closely related to the climatic conditions of the temperate zone and its ecological characteristics. The basis of the classical geomorphological classification of dolines was the characteristic geological condition and the resulting form. Doline formation is shaped by the processes of complex geoecological factors (rock, climate, water, soil, vegetation). Dolines are vulnerable spots in karst areas. The environmental load originating from anthropogenic utilization endangers the natural course of corrosion and the quality of the non-renewable resources of karsts as well as karst ecosystem services, therefore, a complex assessment is necessary for revealing the changes. The study investigates the affect of some important geoecological parameters on the development of solution dolines

Influence of meteorological variables to water quality in five lakes over the Aggtelek (Hungary) and Slovak karst regions – a case study

The main objective of this study is to analyse the effect of tendencies in the meteorological variables on the water quality on the example of five lakes in the Aggtelek and Slovak karst. The data set used eleven water quality parameters (oxygen saturation, chemical oxygen demand, nitrate, nitrite, orthophosphate, total phosphorus, ammonium, pH, conductivity, iron, manganese), as well as daily data of six climatic parameters from the period 2008-2010. A cluster analysis is performed in order to determine the climate impact on the water quality parameters. Furthermore, factor analysis with special transformation, as a novelty in the study, is implemented to find out the weight of the climate parameters as explanatory variables and hence their rank of importance in forming the given water quality parameter as an influencing variable. The study introduces a methodology for analysing the climate impact on the water quality parameters. In order to reduce the number of the water quality parameters, a so called two-stage factor analysis was performed, which is a novel procedure. Application of the two-stage factor analysis involves both benefits and disadvantages. Its benefit is that it substantially reduces the number of resultant variables. In this way, information loss of the retained factors is around 20%. As a result, we received that both positive and negative extreme values of water quality parameters can be associated with weak or breaking-up warm fronts passing through over the region. On the contrary, the role of anticyclones or anticyclone ridge weather situations is supposed to be irrelevant. Unstable and extreme weather conditions act in the direction of breaking up the balance that would support the good water quality. This process does not benefit the water use nor the sensitive karst hydrogeological system

Egy specializált növényi szerv, a szimbiotikus gyökérgümő kialakulásához kapcsolódó folyamatok funkcionális genomikai vizsgálata. = Functional genomic analysis of the symbiotic root nodule organogenesis.

A nitrogénkötő szimbiózis kialakulása során a pillangós virágú növényeken egy új szerv, a gyökérgümő jön létre, melyben az endoszimbionta baktériumok redukálják a légköri nitrogént a növény számára. A lucernával rokon Medicago truncatula modellnövényt vizsgáljuk, hogy megismerjük ennek a biológiai folyamatnak a molekuláris hátterét. A pályázaton belül egy szimbiotikus génnek (Lin) a mutáns fenotípus térképezésén alapuló klónozását és elsődleges leírását vállaltuk. A M. truncatula lin mutáns gyökerén a szimbionta baktérium adásakor a kezdeti növényi válaszreakciók indukálódnak, a sejtosztódás következtében a gümőprimordium kialakul a belső kéregsejtekből. A baktériumok bejutnak a gyökérszőrbe, azonban az infekció elhal a gyökér epidermiszben. A mutációt szenvedett génnek tehát elengedhetetlen funkciója van a gyökérgümő kialakulásában. Genetikai térképezéssel a mutációt helyét az egyes kapcsoltsági csoporton a DSI és SCP nevű molekuláris markerek között határoztuk meg. E két markert használtuk kiindulási pontként a genomsétához, melynek révén eljutottunk a mutációt hordozó régió meghatározásához, fizikai térképezéséhez, szekvenálásához. A lin mutációt egy ~ 1500 aminosav hosszúságú fehérjét kódoló génben azonosítottuk. A kódolt fehérje hordoz egy ún. U-box domént, mely szerint feltételezhető a fehérje ubiquitin ligáz aktivitása. Ezáltal a LIN fehérje feltételezett funkciója egy, a szimbiózis kialakulásában még nem vizsgált út, az ubiquitinációs folyamatok fontosságára mutat rá. | Symbiotic root nodules are special organs developed on the roots of legume plants upon rhizobial inoculation, in which biological nitrogen fixation takes place. We use the model legume Medicago truncatula as an object to acquire more information about the molecular background of this biological process. We have used positional cloning to isolate a new symbiotic gene playing important role in the nodule organogenesis as well as in the bacterial invasion Medicago truncatula. The M. truncatula lin (lumpy infections) mutant, defective in intermediate steps of nodule differentiation, has been identified as an EMS mutant of line Jemalong A17. This mutant is characterized by a 4-fold reduction in the number of infections, all of which arrest in the root epidermis, and by nodule primordia that initiate normally but fail to mature. For genetic mapping lin a mapping population was generated and the map position of lin has been determined between markers DSI and SCP on Linkage Group 1. These molecular markers were used to start the physical mapping and genome walking towards lin. The genomic region carrying the mutated gene was delimited by the help of recombinants, followed by sequencing. Sequence analyses revealed many candidate genes among which the lin mutation was identified in a gene coding for a large protein of ~ 1500 AA. Based on strong sequence homology the LIN protein contains a U-box domain and thereby is predicted to act as an E3 ubiquitin ligase

Összehasonlító géntérképezés és szekvenciaszintű összehasonlítás pillangósok és egyéb kétszikűek genomja között = Comparative mapping and sequence analysis of the genomes of legumes and other dicotyledonous plants

A diploid lucerna térképezése során azonosítottunk egy egyedet, melyben az RPS13 (ribosomal protein S13) génhez homológ lókusz deléciót szenvedett, de nem volt fenotipikus változás. Megállapítottuk, hogy a deléció az RPS13 gén egy csonka változatát érintette, ezért arra következtettünk, hogy ez a génkópia egy mRNS molekulán keresztül retrotranszpozícióval épült vissza a genomba, és a gén nem funkcionál. Egy M. truncatula levélfejlődési mutáns mutációjának állapítottuk meg térképezésen alapuló génizolálás segítségével először a térképhelyét a kettes kapcsoltsági csoporton, majd a fenotípusért felelős mutációt (egy G->A nukleotid csere, amely glutaminsav->lizin aminosav cseréhez vezet). Az érintett génről kiderült, hogy az Arabidopsis thaliana Immutans génnel nagyfokú homológiát mutató, ezért a M. truncatula Immutans homologjának tekintjük. Az Immutans gén egy plasztokinon oxigén: oxidoreduktázt kódol, melynek szerepe van a karotenoid bioszintetikus útvonalban és terminális oxidázként funkcionál a plasztiszokban. Szekvencia homológiák és analízis alapján elmondhatjuk, hogy a kimutatott aminosavcsere a mutáns növényekben az enzim vasion kötésében résztvevő egyik aminosavát érintette, ami a mutáns fenotípushoz vezethetett. Közel 100 gén összehasonlító térképezéséből megállapíthattuk, hogy a Medicago truncatula és a borsó genomjai nagy mértékben kolineárisak, s az eltérések, mint a különböző kromoszómaszám is, pár nagyobb genomiális átrendezéssel megmagyarázható. | We have identified a mutant individual during the genetic mapping of the diploid alfalfa, in which a deletion could be demonstrated in one of the locus having sequence homology to the RPS13 gene. This deletion however had no phenotypic effect. It was demonstrated that this allele contained a truncated copy of the RPS13 gene. This truncated gene was absent in the deletion derivative. This copy was the consequence of the reinsertion of a DNA copy of RPS13 mRNA through retrotransposition, consequently, this was not a functional copy. We have identified the map position as well as the nature of the mutation by map based cloning of a mutant gene which originated from a Medicago truncatula mutant displaying leaf variegated phenotype. The mutation was G-A nukleotid transition leading to a glutamate-lysine amino acid changes. The effected gene was homologous to the Arabidopsis thaliana Immutans gene, therefore the gene was considered as the M. truncatula Immutans ortholog. The immutans gene is encoding a plastochinon oxigen:oxidoreductase, which is involved in the carotenoide biosynthesis. From the result it can be concluded that the amino acid change identified was the consequence of the variegated phenotype of the M. truncatula mutant. Almost 100 genes have been mapped in both alfalfa and pea. Comparative mapping revealed that the two genomes are highly syntenic, and that the differences, like the different chromosome numbers too, are the consequences of few large genomic rearrangements

Conserved CDC20 Cell Cycle Functions Are Carried out by Two of the Five Isoforms in Arabidopsis thaliana

The CDC20 and Cdh1/CCS52 proteins are substrate determinants and activators of the Anaphase Promoting Complex/Cyclosome (APC/C) E3 ubiquitin ligase and as such they control the mitotic cell cycle by targeting the degradation of various cell cycle regulators. In yeasts and animals the main CDC20 function is the destruction of securin and mitotic cyclins. Plants have multiple CDC20 gene copies whose functions have not been explored yet. In Arabidopsis thaliana there are five CDC20 isoforms and here we aimed at defining their contribution to cell cycle regulation, substrate selectivity and plant development.Studying the gene structure and phylogeny of plant CDC20s, the expression of the five AtCDC20 gene copies and their interactions with the APC/C subunit APC10, the CCS52 proteins, components of the mitotic checkpoint complex (MCC) and mitotic cyclin substrates, conserved CDC20 functions could be assigned for AtCDC20.1 and AtCDC20.2. The other three intron-less genes were silent and specific for Arabidopsis. We show that AtCDC20.1 and AtCDC20.2 are components of the MCC and interact with mitotic cyclins with unexpected specificity. AtCDC20.1 and AtCDC20.2 are expressed in meristems, organ primordia and AtCDC20.1 also in pollen grains and developing seeds. Knocking down both genes simultaneously by RNAi resulted in severe delay in plant development and male sterility. In these lines, the meristem size was reduced while the cell size and ploidy levels were unaffected indicating that the lower cell number and likely slowdown of the cell cycle are the cause of reduced plant growth.The intron-containing CDC20 gene copies provide conserved and redundant functions for cell cycle progression in plants and are required for meristem maintenance, plant growth and male gametophyte formation. The Arabidopsis-specific intron-less genes are possibly "retrogenes" and have hitherto undefined functions or are pseudogenes

DNA methylation in an intron of the IBM1 histone demethylase gene stabilizes chromatin modification patterns

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