Wyniki wyszukiwania - Biblioteka Nauki

1

Genetic variability of potato spindle tuber viroid RNA replicon.

100%

Góra-Sochacka A. , Candresse T. , Zagórski W.

Acta Biochimica Polonica

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2001

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tom 48

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nr 2

467-476

EN

The genetic continuity of the potato spindle tuber viroid (PSTVd) genome was analysed after infection of tomato plants with cloned cDNAs of parental strains. During the six weeks of the experiment, several new sequence variants appeared. The sequence variants detected in the progeny population induced sequence-specific disease symptoms. The PSTVd genome therefore follows the pattern expected for typical pseudo-strains propagating in plants as a population of similar sequences. Assessing further the replicon continuity, a PSTVd cDNA mutant with a deletion in the central conserved region was constructed and proven to be non-infectious. Surprisingly, in a sub-population of potato transformants expressing the same deleted PSTVd RNA an infectious viroid was detected. This suggests specific transcript conversion followed by recovery of the full-length pathogen genome.

2

Co-inoculation with two non-infectious cDNA copies of potato spindle tuber viroid [PSTVd] leads to the appearance of novel fully infectious variants

86%

Podstolski W. , Gora-Sochacka A. , Zagorski W.

Acta Biochimica Polonica

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2005

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tom 52

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nr 1

EN

Potato spindle tuber viroid (PSTVd) is one of the smallest (about 360 nt) infectious plant agents. It is composed of a single-stranded circular non-coding RNA molecule. In the course of previous passage experiments with two intermediate PSTVd variants I2 and I4, three non-infectious clones (I2-50, I4-37 and I4 VI-17) were found. When inoculated separately as cDNAs on tomato “Rutgers” test plants these variants did not induce any visible disease symptoms and did not produce progeny. The presence of such non-infectious variants raises several questions about their origin and biology and to answer them, mixed co-infections with cDNA copies of two non-infectious variants (I2-50, I4-37) were performed. PSTVd infection was observed in seven out of 30 inoculated plants. The progeny isolated from three separate plants contained novel variants, together with the parental I2 and I4 sequences. It is conceivable that the appearance of repaired PSTVd molecules, clearly capable of cell-to-cell movement leading to the systemic infection, results from recombination events. An analysis of the recombinant molecules and comparison with databases identified the specific sites responsible for the restricted infectivity of the I2-50 and I4-37 PSTVd variants. In parallel experiments in which (+) strand PSTVd infectious transcripts were used, no recombinants were observed, and the original I2-50 and I4-37 non-infectious sequences were not detected in the progeny.

3

The reaction of field-grown tomato cultivars to infection with potato spindle tuber viroid [PSTV]

86%

Kryczynski S. , Stawiszynska A. , Abuhliga T. A.

Phytopathologia Polonica

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1995

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tom 10

4

Attempts to use RT-PCR technique in research on viroid transport in plants

86%

Kryczynski S. , Stawiszynska A. , Wypijewski K. , Rezler A.

Phytopathologia Polonica

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1999

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tom 17

5

Cytopathological changes in nucleus of Lycopersicon esculentum cult. Rutgers plants infected with potato spindle tuber viroid [PSTVd]

72%

Rudzinska-Langwald A.

Annals of Warsaw Agricultural University. Agriculture

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1999

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nr 35

3-12

6

Translocation and distribution of potato spindle tuber viroid in infected plants

72%

Kryczynski S. , Stawiszynska A. , Abuhliga T. A.

Phytopathologia Polonica

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1999

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tom 17

7

Structure of the pathogenicity domain and disease symptoms induced by potato spindle tuber viroid [PSTVd]

72%

Gora-Sochacka A. , Pawlowicz J. , Candresse T. , Zagorski W.

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1996

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tom 44

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nr 3-4

8

Digoxigenin-labelled molecular probe for the simultaneous detection of three potato pathogens: potato spindle tuber viroid [PSTVd], potato virus Y [PVY], and potato leafroll virus /PLRV/

72%

Welnicki M. , Zekanowski C. , Zagorski W.

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nr 4

XX

A molecular probe, p3POT, was constructed of PSTVd, PVY, PLRV cDNA fragments introduced into pUCl8 vector. Sequencing of the inserts revealed that cloned fragments covered conservative parts of pathogenic genomes. Dot-blot hybridization of digoxigenin-labelled construct to crude extracts from plants infected with different potato viruses proved high sensitivity and specificity of the p3POT probe. This makes p3POT probe an useful tool for the routine testing, and selection of virus-free potatoes

9

Zabezpieczenie ziemniakow przed porazeniem wiroidem wrzecionowatosci bulw. Zalecenia

58%

Kaczmarek U. , Turska E.

Ziemniak Polski

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1992

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nr 4

17-22

10

Zastosowanie metody dynamiki molekularnej w przestrzeni katow torsyjnych [TAD] jako proba wyznaczenia struktur trzeciorzedowych wiroida wrzecionowatosci bulw ziemniaka [PSTVd]

58%

Folkman W. , Popenda M. , Cajza M.

Progress in Plant Protection

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2006

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tom 46

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nr 2

588-591

11

Analiza struktur przestrzennych wiroida wrzecionowatości bulw ziemniaka (PSTVd)

58%

Folkman W. , Popienda M. , Cajza M.

Progress in Plant Protection

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2010

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tom 50

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nr 2

EN

Based on 156 sequences of Potato spindle tuber viroid (PSTVd) taken from GenBank, consensus sequence thereof containing 359 nucleotides was determied by means of CLUSTAL W program. For this sequence the secondary structures were derived by using Mfold program. In linear structure of the lowest two apical loops and 27 internal loops and bulges were found. To define 3D structures of those fragments and double-stranded structures connecting them, an RNA FRABASE ver. 1.0 search engine was used. In this way, their 3D equivalents in resolved crystallographic structures and those derived from measurements of NMR spectra were found. For smaller fragments, full compatibility was observed. Bigger ones required usage of our script to isostericity base replacement for fragments of not full homology. The above procedure did not change torsion angles χ around glycosyl bonds. Then these fragments were connected via superimposition of common canonical base pairs. An integrated structure that obtained was then energetically minimized in torsion angles space and Cartesian coordinates space. Then 7 different 2D structures (2 linear and 5 branched) were taken into account and additional, alternative threedimensional ones were generated for them. The length of whole 3D structure of viroid RNA for corresponding linear 2D structure amounted to 500 Å that was in agreement with the data obtained from electron microscopy. RNA of linear structures, due to their extent is able to easily complex with proteins. Asides from previously found in central conservative domain of PSTVd and described in the literature E loop we found another, similar one in pathogenic domain. Both structures have characteristic of sarcin/ricin RNA motif S-turn of one strain.

12

Choroby ziemniaka pod szczególnym nadzorem. Podlegają przepisom kwarantannowym

44%

Wolny S.

Agrochemia

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2000

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nr 06

13

Podlegaja obowiazkowi zwalczania...

22%

Wolny S.

Agrochemia

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1999

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nr 07

37-41