Authors:Gyöngyvér Gell, Kathrin Petrik, Endre Sebestyén, and Ervin Balázs
A potyvírusok családjába tartozó kukorica csíkos mozaik vírus (Maize dwarf mosaic virus, MDMV) az egyszikű növények egyik legjelentősebb kórokozója. Az MDMV genetikai állományának nagyfokú változékonysága és ennek lehetséges patológiai következményei figyelmünket a vírus tüneti determinánsainak és populációjának részletesebb elemzésére irányította. Vizsgálataink a köpenyfehérjét (CP- coat protein) kódoló régió összehasonlító analízisére terjednek ki.
Mintáinkat négy egymást követő évben (2006–2009) két, földrajzilag jól elkülönülő területről, a szegedi Gabonatermesztési Kht. tenyészkertjéből kukoricáról (Zea mays L. convar. saccharata), fenyércirokról (Sorghum halepense (L.) Pers) és szemes cirokról (Sorghum bicolor (L.) Moench), valamint martonvásári tenyészparcellákról gyűjtöttük. A polimeráz láncreakció (PCR) módszerrel felszaporított köpenyfehérje gének nukleinsav sorrendjét meghatároztuk, majd feltérképeztük a vírus molekuláris rokonsági körét. Az izolátumok közti eltérés 0–13,6%-ig terjed, attól függően, hogy a köpenyfehérje gén N-terminális, központi- illetve C-terminális régióját vizsgáltuk. Az összesen nyolcvanhat MDMV izolátum közül öt esetben (Mv0702, Mv0801, Mv0811, Mv0814 és Mv0905) találtunk a köpenyfehérje N-terminális régiójában 13 aminosav hosszúságú inszerciót, ezek az izolátumok az adatbázisban megtalálható Argentin és Spanyol izolátumokkal egy külön csoportot alkotnak. A kapott eredmények azt igazolják, hogy az izolátumok a mintagyűjtés évétől és földrajzi helyétől függetlenül oszlanak el a törzsfán, a populáció stabil.
Authors:A. Almási, I. Tóbiás, I. Manoussopoulos, Zs. Basky, and L. Palkovics
Nucleotide and amino acid sequences of the helper component protease (HC-Pro) and the coat protein (CP) of two Hungarian
Potato virus Y
(PVY) isolates, differing in aphid transmissibility were determined. Isolate PVY-5 belongs to the common “O” strain (PVY
), whereas isolates PVY-98 and PVY-111 belong to the “N” (PVY
) and the PVY-NTN and PVY-H to the “NTN” (PVY
) strains, respectively. The PVY-5 isolate varied significantly from the others in aphid transmission and in the ability to systemically infect potato plants. To elucidate whether these differences were due to mutations affecting known functional motifs, the corresponding cistrons of the two proteins were sequenced and aligned. Our analysis showed that none of the well-known motifs, responsible for aphid transmission in the two proteins had been affected. However, the defective isolate had two natural mutations in the HC-Pro in the vicinity of the PTK motif, and a number of mutations in the CP, distributed both in the N-terminus and the central region. As these two proteins are the only known viral participants in the aphid transmission mechanism, it is likely that some of the observed mutations might be involved in this process. Thus, our results indicate that other, previously unidentified sequences or factors may influence virus-vector interactions and transmission of PVY.
Lima, E.A.B.F., C.P. Ferreira and W.A.C. Godoy. 2009. Ecological modeling and pest population management: a possible and necessary connection in a changing world. Neotrop. Entomol. 38: 699–707.
The changes in the polypeptide patterns of soluble proteins of wheat flag leaves after treatment with two synthetic cytokinin-like substances 3-CP-2-PU [1-(3-chlorophenyl)-3-(2-pyridyl)urea] and 3-CP-4-MPU [1-(3-chlorophenyl)-3-(4-methyl-2-pyridyl)urea] was studied. Both compounds increased differentially in quantity and composition most individual polypeptides identified compared to the non-treated leaves. While 3-CP-2-PU increased only the polypeptide quantity, 3-CP-4-MPU led to the appearance of new polypeptide with Mw of 51 kDa.
Authors:S. Raveendar, G.A. Lee, K.J. Lee, M.J. Shin, J.R. Lee, S.Y. Lee, G.T. Cho, K.H. Ma, and J.W. Chung
The complete chloroplast (cp) genome sequence of Pearl millet (Pennisetum glaucum [L.] R. Br.), an important grain and forage crop in the family Poaceae, is reported in this study. The complete cp genome sequence of P. glaucum is 138,172 bp in length with 38.6% overall GC content and exhibits a typical quadripartite structure comprising one pair of inverted repeat (IR) regions (22,275 bp) separated by a small single-copy (SSC) region (12,409 bp) and a large single-copy (LSC) region (81,213). The P. glaucum cp genome encodes 110 unique genes, 76 of which are protein-coding genes, 4 ribosomal RNA (rRNA) genes, 30 transfer RNA (tRNA) genes and 18 duplicated genes in the IR region. Nine genes contain one or two introns. Whole genome alignments of cp genome were performed for genome-wide comparison. Locally collinear blocks (LCBs) identified among the cp genomes showed that they were well conserved with respect to gene organization and order. This newly determined cp genome sequence of P. glaucum will provide valuable information for the future breeding programs of valuable cereal crops in the family Poaceae.
Authors:T. Müller, B. Váradi, P. Horn, and M. Bercsényi
Previously described and alternative methods of the induction of sexual maturation in the European eel were investigated. Weekly administrations of a gonadoliberin agonist (GnRH-A=D-Phe6-GnRH-Ea) did not induce statistically significant effect on the gonads of treated eels in none of the dosages used (0.1 mg and 10 mg/fish). Carp pituitary extract and carp pituitary extract together with a dopamine antagonist caused considerable external changes (increase in eye size) and significant gonadal development in two treatment groups: wild and cultivated stocks. The induction of the ovulation by double amount of CP and gonadoliberin agonist with dopamine antagonist mixture was not successful in a wild stock. Fertilisation of stripped eggs of farm eel was attempted unsuccessfully in, due to low egg quality. An advanced phase of the sexual maturation process could be induced in specimen infected by Anguillicola crassus indicating, that nematode infection is not a limiting factor in the artificial propagation of the European eel.
Authors:Letitia Oprean, Enikő Gaspar, Ecaterina Lengyel, and V. Cristea
Twenty yeast strains have recently been isolated in pure cultures from natural and industrial sources and identified based mainly on physiological properties. The majority of the strains (15) are alcohologenic belonging to the genus Saccharomyces and comprise two brewer's (beer) yeast strains (S. carlsbergensis=S. uvarum A and B), two baker's yeast strains (S. cerevisiae CA and CP), one spirit yeast strain (S. cerevisiae CF) and ten wine yeast strains (S. cerevisiae var. ellipsoideus=S. ellipsoideus 1, 3, 4, 6, 8 and 9; S. oviformis 2, 5 and 7; and S. uvarum 10). The other 5 yeast strains belong to different species: Kloeckera apiculate, Candida mycoderma (Mycoderma vini), Pichia membranaefaciens, Rhodotorula glutinis and Torulopsis holmii, respectively.
The complete genome of Hosta Virus X (HVX), which is thought to be a distinct species of Potexvirus, was sequenced. Nucleotide sequences of HVX were compared with those of other members of the genus Potexvirus and phylogenetic tree was constructed. The range of identities of viral replicase open reading frame 1 (ORF1) between HVX and other potexviruses were 43.1%–55.1% and 35.9%–46.6% at the nucleotide and amino acid levels, respectively. Phylogenetic analysis was performed according to the amino acid sequence of the replicase to determine the position of HVX in the genus Potexvirus. Results from the phylogenetic analysis demonstrated that HVX was in the same group as Cassava common mosaic virus (CsCMV), Plantago asiatica mosaic virus (PlAMV), Tulip virus X (TVX), and Hydrangea ring spot virus (HdRSV). In particular, coat protein (CP) sequences among viruses from different Hosta cultivars were revealed to be less variable than those from different isolates of Potato virus X (PVX), a Potexvirus type species. In the present study, HVX was transmissible by seeds of the Hosta “Blue Cadet” cultivar. Moreover, HVX was detected in the embryo but not in the seed coat or endosperm of the seed.
Authors:A. Boustani, F. Fatehi, and R. Azizinezhad
Salinity is a major constraint to crop productivity and mechanisms of plant responses to salinity stress are extremely complex. “Hordeum marinum” is a salt tolerant barley species, which could be a good source to evaluate salt-tolerance patterns. Proteomics is a powerful technique to identify proteins involved in plant adaptation to stresses. We applied a proteomic approach to better understanding the mechanism of plant responses to salinity in a salt-tolerant genotype of barley. At the 4-leaf stage, plants were exposed to 0 (control treatment) or 300 mM NaCl (salt treatment). Salt treatment was maintained for 3 weeks. Total proteins of leaf 4 were extracted and separated by two-dimensional gel electrophoresis. More than 290 protein spots were reproducibly detected. Of these, 20 spots showed significant changes to salt treatment compared to the control: 19 spots were upregulated and 1 spot was absent. Using MALDI-TOF/TOF MS, we identified 20 cellular proteins which represented 11 different proteins and were classified into five categories. These proteins were involved in various cellular functions. Upregulation of proteins which involved in protein processing (ribosomal protein, cullin family, cp31AHv protein and RNA recognition motif (RRM) superfamily), photosynthesis (Ribulose-1,5-bisphosphate carboxylase/oxygenase (rubisco) and Ribulose bisphosphate carboxylase/oxygenase activase (rubisco activase)), energy metabolism (cytosolic malate dehydrogenase (cyMDH) and fructokinase), oxygen species scavenging and defense (cystatin and thioredoxin) may increase plant adaptation to salt stress.