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41.
Somatic mutation and recombination test on wing cells of Drosophila melanogaster showed that the recombination frequency in the somatic tissues of strains studied correlated with the presence of a full-length copy of the hobo transposable element in the genome. Transposition of hobo in somatic tissue cells at a frequency 3.5 x 10-2 per site per X chromosome was shown by fluorescence in situ hybridization with salivary gland polytene chromosomes of larvae of one of the D. melanogaster strains having a full-length hobo copy.  相似文献   
42.
Virtual fragment screening could be a promising alternative to existing experimental screening techniques. However, reliable methods of in silico fragment screening are yet to be established and validated. In order to develop such an approach we first checked how successful the existing molecular docking methods can be in predicting fragment binding affinities and poses. Using our Lead Finder docking software the RMSD of the binding energy prediction was observed to be 1.35 kcal/mol(-1) on a set of 26 experimentally characterized fragment inhibitors, and the RMSD of the predicted binding pose from the experimental one was <1.5 ?. Then, we explored docking of 68 fragments obtained from 39 drug molecules for which co-crystal structures were available from the PDB. It appeared that fragments that participate in oriented non-covalent interactions, such as hydrogen bonds and metal coordination, could be correctly docked in 70-80% of cases suggesting the potential success of rediscovering of corresponding drugs by in silico fragment approach. Based on these findings we've developed a virtual fragment screening technique which involved structural filtration of protein-ligand complexes for specific interactions and subsequent clustering in order to minimize the number of preferable starting fragment candidates. Application of this method led to 2 millimolar-scale fragment PARP1 inhibitors with a new scaffold.  相似文献   
43.
Mitochondrial ribosomal RNA coding regions in the only three green algal taxa investigated to date are fundamentally different in that they are continuous in Prototheca wickerhamii, but highly fragmented and scrambled in Chlamydomonas reinhardtii and Chlamydomonas eugametos. To gain more insight into the mode of evolution of fragmented and scrambled mitochondrial ribosomal RNA (rRNA) genes within the green algal group, this work (1) provides additional information on fragmentation patterns of mitochondrial small- and large-subunit (SSU and LSU) rRNAs that strongly supports the concept of a gradual increase in the extent of discontinuity of mitochondrial rRNAs among chlorophycean green algae and (2) reports the first example of fragmented and scrambled mitochondrial LSU rRNA coding regions in a green algal taxon outside the Chlamydomonas group. The present study (1) suggests that the scrambling of the mitochondrial rRNA coding regions may have occurred early in the evolution of fragmented and scrambled mitochondrial rRNA genes within the chlorophycean green algal group, most likely in parallel with the fragmentation events, (2) proposes recombination as a possible mechanism involved in the evolution of these mitochondrial rRNA genes, and (3) presents a hypothetical pathway for converting continuous mitochondrial rRNA genes into the highly fragmented and scrambled rRNA coding regions of Chlamydomonas through a series of recombinatorial events between short repeated sequences.   相似文献   
44.
Massive parallel sequencing of the 16S rRNA gene fragments was used to investigate the composition and diversity of microbial communities in sediments from Southern Baikal to a depth of 9 cm with 1-cm step. In the layers from the sediment surface to the lower border of oxygen penetration (2 cm), organotrophic bacteria with high similarity to the heterotrophic species Luteolibacter luojiensis constituted the largest fraction of the community. In the formation zone of Fe/Mn crusts (3–5 cm), Proteobacteria and Actinobacteria predominated in the community, while the share of Cyanobacteria was considerable. The lower reduced layers showed an increased contribution of the Bacteroidetes, while the shares of the taxa predominant in the higher layers remained significant. Analysis of archaeal 16S rRNA gene amplicons revealed predominance of the soil and aquatic Thaumarchaeota (Marine Group I lineage), which are involved in anaerobic ammonium oxidation, practically in all sediment layers. The buried oxidized layer (6–7 cm), where members of the uncultured Marine Benthic Group D lineage of the order Thermoplasmatales (Euryarchaeota) predominated, was an exception in this regard. Small numbers of archaea of the Baikal-1 lineages (below 1%) were observed in the communities from the 6–7 and 7–8 cm layers, while the archaea involved in anaerobic methane oxidation (including the ANME-2d group) were not detected.  相似文献   
45.

Background  

Simple Sequence Repeat (SSR) or microsatellite markers are valuable for genetic research. Experimental methods to develop SSR markers are laborious, time consuming and expensive. In silico approaches have become a practicable and relatively inexpensive alternative during the last decade, although testing putative SSR markers still is time consuming and expensive. In many species only a relatively small percentage of SSR markers turn out to be polymorphic. This is particularly true for markers derived from expressed sequence tags (ESTs). In EST databases a large redundancy of sequences is present, which may contain information on length-polymorphisms in the SSR they contain, and whether they have been derived from heterozygotes or from different genotypes. Up to now, although a number of programs have been developed to identify SSRs in EST sequences, no software can detect putatively polymorphic SSRs.  相似文献   
46.

Background  

Over 50% of patients with upper limb paresis resulting from stroke face long-term impaired arm function and ensuing disability in daily life. Unfortunately, the number of effective treatments aimed at improving arm function due to stroke is still low. This study aims to evaluate a new therapy for improving arm function in sub-acute stroke patients based on mental practice theories and functional task-oriented training, and to study the predictors for a positive treatment result. It is hypothesized that a six-week, mental practice-based training program (additional to regular therapy) targeting the specific upper extremity skills important to the individual patient will significantly improve both arm function and daily activity performance, as well as being cost effective.  相似文献   
47.
Two placoderms of different orders from a concretion of the Zyabrevo locality (Evlanovo Regional Stage, Frasnian) in central Russia are described. Five plates of the ventral and lateral sides of the trunk armor are assigned to a plourdosteid arthrodire. Three bones located in the region of its stomach are determined as a juvenile ptyctodontid, Ctenurella sp. Records providing actual evidence of predation in Devonian vertebrates are extremely scarce. Finds of this kind are listed for the first time.  相似文献   
48.
49.

Background  

Demodex gatoi is unique among demodectic mites. It possesses a distinct stubby appearance, and, instead of residing in the hair follicles, it dwells in the keratin layer of the epidermis, causing a pruritic and contagious skin disease in cats. Little is known of the occurrence of D. gatoi in Europe or control of D. gatoi infestation.  相似文献   
50.
The retaining endo-1,3-β-d-glucanase (EC 3.2.1.39) was isolated from the crystalline styles of the commercially available Vietnamese edible mussel Perna viridis. It catalyzes hydrolysis of β-1,3-bonds in glucans and enables to catalyze a transglycosylation reaction. Resources of mass-spectrometry for analysis of enzymatic products were studied. cDNA sequence of endo-1,3-β-d-glucanase was determined by RT-PCR in conjunction with the rapid amplification of cDNA ends (RACE) methods. The cDNA of 1380bp contains an open reading frame of 1332bp encoding a mature protein of 328 amino acids. On basis of amino acid sequence analysis endo-1,3-β-d-glucanase was classified as a glycoside hydrolase of family 16.  相似文献   
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