Satellite DNAs are the major repetitive DNA components in eukaryotic genomes. Although satellite DNA has long been called "parasite DNA" there is substantial evidence that it could be associated with some functions of chromosome biology. Ladybird beetles (Coccinellidae) are one of the largest and most important groups of beetles. Many ladybirds are of economic interest as biological control agents because they eat some agricultural pests such as aphids and scale insects. However, other species are phytophagous and can damage crops. Despite the ecological importance of the latter group there are no studies on their satellite DNA. A satellite DNA family was isolated and characterized in the ladybird Henosepilachna argus. This satellite DNA is organized in tandem repeats of 658 bp and is A + T rich (67.3%). The recorded high sequence conservation of the monomers together with the detection of putative gene conversion processes indicate concerted evolution. Reverse transcription polymerase chain reaction (RT-PCR) revealed that this satellite DNA is transcribed and in situ hybridization its location in the subtelomeric regions of all chromosomes except the long arm of the X chromosome. The presence of this satellite DNA in other species of the genus Henosepilachna and Epilachna was also tested using PCR. The results indicate that this satellite DNA sequence is so far specific to H. argus., Pablo Mora, Jesús Vela, Areli Ruiz-Mena, Teresa Palomeque, Pedro Lorite., and Obsahuje bibliografii
A novel panel of 16 microsatellite markers, obtained by pyrosequencing of enriched genomic libraries, is reported for the flightless European bushcricket Ephippiger diurnus (Dufour) (Orthoptera: Tettigoniidae). Five multiplex and one simplex PCR protocols were optimized, and the polymorphism at the 16 loci was assessed in two natural populations from southern France. The mean allele number and (expected mean heterozygosity) were 8.94 (0.71) and 6.57 (0.70), respectively, in each population. Several loci were at Hardy-Weinberg disequilibrium (HWD), possibly due to the incidence of null alleles. The occurrence of null alleles has been previously reported for this species, and it is a common feature of microsatellite loci in Orthoptera. Cross-amplification tests demonstrated the transferability of some of these loci to other ephippigerine species. The microsatellite loci reported here substantially increase the number of available loci for this species and will afford an accurate picture of E. diurnus phylogeography, the genetic structure of its populations, and an improved understanding of the evolution of male song and other sexually-selected traits in this highly variable species., Yareli Esquer-Garrigos, Michael D. Greenfield, Virginie Party, Réjane Streiff., and Obsahuje bibliografii
Nucleotidase activity and Ca-uptake were characterized in endoplasmic reticulum (ER) enriched rat submandibular gland (SMG) microsomal preparations. (i ) Ca-uptake had characteristics of an ER Ca-ATPase. (ii) Nucleotidase activity was equally stimulated by calcium, magnesium and manganese, but with different Km values. (iii) Specific inhibitors of P-type Ca-ATPases were ineffective on nucleotidase activity, demonstrating that this activity was not related to calcium uptake and did not correspond to classical Ca2+ pumps. (iv) ATP and UTP were more efficient substrates, whereas ADP and UDP were hydrolyzed at significantly slower rate. (v) Nucleotidase activity was sensitive to mild detergent solubilization and insensitive to ionophore addition. (vi) Nucleotidase activity was strongly inhibited by suramin, a nucleoside triphosphate diphosphohydrolase (NTPDase) inhibitor. (vii) Nucleotidase activity exponentially diminished as function of time. All these observations are consistent with a NTPDase identity. The presence of a NTPDase was demonstrated by immunohistochemistry in rat SMG. Immunoreactivity was stronger in ductal cells than in mucous and serous acini. Although this enzyme was observed in the plasma membrane, colocalization with the ER marker calnexin revealed a specific subcellular localization in this organelle of all three types of cell. The putative function of this NTPDase activity in salivary glands is discussed., M. A. Ostuni ...[et al.]., and Obsahuje seznam literatury
The major light-harvesting chlorophyll (Chl) a/b complexes of photosystem II (LHCIIb) play important roles in energy balance of thylakoid membrane. They harvest solar energy, transfer the energy to the reaction center under normal light condition and dissipate excess excitation energy under strong light condition. Many bamboo species could grow very fast even under extremely changing light conditions. In order to explain whether LHCIIb in bamboo contributes to this specific characteristic, the spectroscopic features, the capacity of forming homotrimers and structural stabilities of different isoforms (Lhcb1-3) were investigated. The apoproteins of the three isoforms of LHCIIb in bamboo are overexpressed in vitro and successfully refolded with thylakoid pigments. The sequences of Lhcb1 and Lhcb2 are similar and they are capable of forming homotrimer, while Lhcb3 lacks 10 residues in the N terminus and can not form the homotrimeric structure. The pigment stoichiometries, spectroscopic characteristics, thermo- and photostabilities of different reconstituted Lhcbs reveal that Lhcb3 differs strongly from Lhcb1 and Lhcb2. Lhcb3 possesses the lowest Qy transition energy and the highest thermostability. Lhcb2 is the most stable monomer under strong illumination among all the isoforms. These results suggest that in spite of small differences, different Lhcb isoforms in bamboo possess similar characteristics as those in other higher plants., Z. H. Jiang ... [et al.]., and Obsahuje bibliografii
Halomicronema hongdechloris is a chlorophyll (Chl) f-producing cyanobacterium. Chl f biosynthesis is induced under far-red light, extending its photosynthetically active radiation range to 760 nm. In this study, PSI complexes were isolated and purified from H. hongdechloris, grown under white light (WL) and far-red light (FR), by a combination of density gradient ultracentrifugation and chromatographic separation. WL-PSI showed similar pigment composition as that of Synechocystis 6803, using Chl a in the reaction center. Both Chl a and f were detected in the FR-PSI, although Chl f was a minor component (~8% of total Chl). The
FR-PSI showed a maximal fluorescence emission peak of 750 nm at 77 K, which is red-shifted ~20 nm compared to the 730 nm recorded from the WL-PSI. The absorption peaks of P700 for WLPSI and FR-PSI were 699 nm and 702 nm, respectively. The function of Chl f in FR-PSI is discussed., Y. Li, N. Vella, M. Chen., and Obsahuje bibliografické odkazy
The Niobe Fritillary, Argynnis niobe, is a habitat specialist and as a consequence is highly endangered in contemporary Europe. To investigate its genetic diversity and population structure, 10 polymorphic microsatellite loci were developed and characterized, using a recently developed pyrosequencing method. The number of alleles per locus ranged from 2 to 21, and the observed and expected heterozygosities varied from 0.17 to 0.53 and from 0.24 to 0.92, respectively. These loci were also successfully used to study the genetic diversity of a closely related species, the High Brown Fritillary, Argynnis adippe, and will be used in future population structure studies of both these species., Jan Zima JR, Dan Leština, Martin Konvička., and Obsahuje seznam literatury
The complete mitochondrial genome (mitogenome) of Spilarctia robusta (Lepidoptera: Noctuoidea: Erebidae) was sequenced and analyzed. The circular mitogenome is made up of 15,447 base pairs (bp). It contains a set of 37 genes, with the gene complement and order similar to that of other lepidopterans. The 12 protein coding genes (PCGs) have a typical mitochondrial start codon (ATN codons), whereas cytochrome c oxidase subunit 1 (cox1) gene utilizes unusually the CAG codon as documented for other lepidopteran mitogenomes. Four of the 13 PCGs have incomplete termination codons, the cox1, nad4 and nad6 with a single T, but cox2 has TA. It comprises six major intergenic spacers, with the exception of the A+T-rich region, spanning at least 10 bp in the mitogenome. The nucleotide composition of the genome is greatly A+T biased (81.09%), with a negative AT skewness (-0.007), indicating the presence of fewer As than Ts, similar to other Noctuoidea. The A+T-rich region is 343 bp long, and contains some conserved regions, including an "ATAGA" motif followed by a 19 bp poly-T stretch, a microsatellite-like (AT)9 and a poly-A element, a characteristic shared with other lepidopteran mitogenomes. Phylogenetic analysis, based on 13 PCGs using Maximum likelihood methods revealed that S. robusta belongs to the superfamily Noctuoidea., Yu Sun, Sen Tian, Cen Qian, Yu-Xuan Sun, Muhammad N. Abbas, Saima Kausar, Lei Wang, Guoqing Wei, Bao-Jian Zhu, Chao-Liang Liu., and Obsahuje bibliografii
A long growing season, mediated by the ability to grow at low temperatures early in the season, can result in higher yields in biomass of crop Miscanthus. In this paper, the chilling tolerance of two highly productive Miscanthus genotypes, the widely planted Miscanthus × giganteus and the Miscanthus sinensis genotype ‘Goliath’, was studied. Measurements in the field as well as under controlled conditions were combined with the main purpose to create basic comparison tools in order to investigate chilling tolerance in Miscanthus in relation to its field performance. Under field conditions, M. × giganteus was higher yielding and had a faster growth rate early in the growing season. Correspondingly, M. × giganteus displayed a less drastic reduction of the leaf elongation rate and of net photosynthesis under continuous chilling stress conditions in the growth chamber. This was accompanied by higher photochemical quenching and lower nonphotochemical quenching in M. × giganteus than that in M. sinensis ‘Goliath’ when exposed to chilling temperatures. No evidence of impaired stomatal conductance or increased use of alternative electron sinks was observed under chilling stress. Soluble sugar content markedly increased in both genotypes when grown at 12°C compared to 20°C. The concentration of raffinose showed the largest relative increase at 12°C, possibly serving as a protection against chilling stress. Overall, both genotypes showed high chilling tolerance for C4 plants, but M. × giganteus performed better than M. sinensis ‘Goliath’. This was not due to its capacity to resume growth earlier in the season but rather due to a higher growth rate and higher photosynthetic efficiency at low temperatures., S. Fonteyne, P. Lootens, H. Muylle, W. van den Ende, T. de Swaef, D. Reheul, I. Roldan-Ruiz., and Obsahuje seznam literatury
This work aimed to evaluate if chilling stress may be mitigated by elevated CO2 (EC) in Beta vulgaris L. plants. Photosynthetic rate was measured at 21% and 2% O2 after a short-term exposure of 5 h at four different treatments: 360 μmol(CO2) mol-1/25°C (AC); 360 μmol(CO2) mol-1/4°C (AC+LT); 700 μmol(CO2) mol-1/25°C (EC); 700 μmol(CO2) mol-1/4°C (EC+LT). Compared to AC+LT, EC+LT plants showed higher values of CO2 fixation, photochemical activity, and Rubisco amount. These latter invest a higher portion of photosynthetic electron flow to O2, differently from AC+LT plants that promote the regulated thermal dissipation processes. In EC+LT plants, the photosynthetic electron flow to O2 acts as a safety mechanism against the excess of absorbed light, upon return to prechilling conditions, allowing photosynthetic apparatus to maintain its efficiency. In AC+LT plants, the increase of thermal dissipation processes was not adequate to guarantee the PSII photoprotection and the photosynthetic recovery after chilling., C. Arena, L. Vitale., and Obsahuje bibliografii
Fourteen predatory species of ladybirds (Coleoptera: Coccinellidae) were collected from May to October 2008 from mountain ash (Sorbus aucuparia) infested with the scale insect Chionaspis salicis at 31 localities in the Ore Mountains, northern Bohemia, Czech Republic. Chilocorus renipustulatus, usually a rare species, made up 85% of the individuals collected (1690). Other abundant species were Coccinella septempunctata, Calvia quatuordecimguttata, Adalia bipunctata and Adalia decempunctata. The invasive alien Harmonia axyridis was present but made up less than one per cent of the individuals collected. Niche overlap between pairs of ladybird species measured in terms of the coefficient of community, Morisita's index and cluster analysis showed that microhabitat preferences were similar and hence the possibility of competition was high in two pairs of congeneric species (Chilocorus and Calvia). Larvae of Ch. renipustulatus were abundant from mid-June through August and were still present in October. and Emanuel Kula, Oldřich Nedvěd.