Cryptic
Dotaz
Zobrazit nápovědu
Previously, the Nine amino acid TransActivation Domain (9aaTAD) was identified in the Gal4 region 862-870 (DDVYNYLFD). Here, we identified 9aaTADs in the distal Gal4 orthologs by our prediction algorithm and found their conservation in the family. The 9aaTAD function as strong activators was demonstrated. We identified adjacent Gal4 region 871-811 (DEDTPPNPKKE) as a natural 9aaTAD inhibitory domain located at the extreme Gal4 terminus. Moreover, we identified conserved Gal4 region 172-185 (FDWSEEDDMSDGLP), which was capable to reverse the 9aaTAD inhibition. In conclusion, our results uncover the existence of the cryptic inhibitory domains, which need to be carefully implemented in all functional studies with transcription factors to avoid incorrect conclusions.
Kryptické druhy sekce Fumigati, tzn. druhy podobné Aspergillus fumigatus, jsou stále častěji uváděny v literatuře jako původci invazivní aspergilózy (IA) u lidí i zvířat. Jejich odhalení a správná identifikace je důležitá, avšak ještě důležitější je stanovení citlivosti daného izolátu k antimykotikům (minimální inhibiční koncentrace, MIC) za použití vhodných metod. Pro tyto kryptické druhy jsou totiž často charakteristické zvýšené hodnoty MIC k lékům volby doporučeným pro terapii IA, jako je vorikonazol nebo amfotericin B.V našem sdělení uvádíme případ plicní aspergilózy u 63letého muže po transplantaci srdce. Jako původce infekce byl kultivačně prokázán a pomocí sekvenace DNA identifikován A. lentulus, se sníženou citlivostí k vorikonazolu a amfotericinu B. Citlivost k antifungálním látkám byla ověřena pomocí standardizované metodiky EUCAST-AFST. Terapie byla na základě získaných hodnot MIC cíleně změněna z vorikonazolu na posakonazol s výborným klinickým efektem. Pokud víme, naše kazuistika je prvním popsaným případem terapie A. lentulusposakonazolem a navíc úspěšným.
Cryptic species within the section Fumigati, that is Aspergillus fumigatus-like species, are increasingly reported in the literature as causative agents of invasive aspergillosis (IA) in both humans and animals. Their detection and proper identification are important, buteven more important is to determine the susceptibility profile (minimum inhibitory concentrations, MICs) of the isolate to antifungalsusing appropriate methods. Cryptic species often demonstrate elevated MICs to drugs recommended for IA therapy such as voriconazole or amphotericin B. Presented is a case of pulmonary aspergillosis in a 63-year-old male heart transplant recipient. Aspergilluslentuluswith reduced susceptibility to voriconazole and amphotericin B was identified as the causative agent of the infection using culture and DNA sequencing. Susceptibility to antifungals was confirmed by the standard EUCAST-AFST methods. Based on MIC values obtained in vitro, therapy was switched from voriconazole to posaconazole with excellent clinical effects. To the best of our knowledge, this is the first reported case of A. lentulusinfection treated with posaconazole and, moreover, a successful one.
With the increasing application of molecular techniques for diatom species discovery and identification, it is important both from a taxonomic as well as an ecological and applied perspective, to understand in which groups morphological species delimitation is congruent with molecular approaches, or needs reconsideration. Moreover, such studies can improve our understanding of morphological trait evolution in this important group of microalgae. In this study, we used morphometric analysis on light microscopy (LM) micrographs in SHERPA, detailed scanning electron microscopy (SEM), and cytological observations in LM to examine 70 clones belonging to eight distinct molecular lineages of the cosmopolitan terrestrial diatom Pinnularia borealis. Due to high within-lineage variation, no conclusive morphological separation in LM nor SEM could be detected. Morphological stasis due to the "low-morphology" problem or stabilizing selection, as well as parallel/convergent evolution, phenotypic plasticity and structural inheritance are discussed as potential drivers for the observations. Altogether, P. borealis is truly cryptic, in contrast to the majority of other diatom species complexes which turned out to be pseudo-cryptic following detailed morphological analysis.
Identifying factors that influence species interactions is central to research in symbiotic systems. While lichens represent iconic models of symbiosis and play important roles in understanding the biology of symbiotic interactions, patterns of interactions in lichen symbionts and mechanisms governing these relationships are not well characterized. This is due, in part to the fact that current taxonomic approaches for recognizing diversity in lichen symbionts commonly fail to accurately reflect actual species diversity. In this study, we employed DNA-based approaches to circumscribed candidate species-level lineages in rock-posy lichen symbionts (mycobiont=Rhizoplaca s. lat. species; photobiont=Trebouxia species). Our results revealed a high degree of cryptic diversity in both the myco- and photobionts in these lichens. Using the candidate species circumscribed here, we investigated the specificity of the symbionts toward their partners and inferred the relative importance of various factors influencing symbiont interactions. Distinct mycobiont species complexes, ecozones, and biomes are significantly correlated with the occurrence of photobiont OTUs, indicating that complex interactions among mycobiont lineages, ecogeography, and microhabitat determine interactions between photobionts and their mycobionts in lichen symbiosis. One-to-one specificity between mycobiont and photobiont species was not found, with the exception of R. maheui that associated with a single Trebouxia OTU that was not found with other Rhizoplaca s. lat. species. We estimated the most recent common ancestor of the core Rhizoplaca group at c. 62.5Ma, similar in age to the diverse parmelioid core group in the well-studied family Parmeliaceae. However, in contrast to Parmeliaceae, species in Rhizoplaca were found to associate with a narrow range of photobionts. Our study provides important perspectives into species diversity and interactions in iconic lichen symbiotic systems and establishes a valuable framework for continuing research into rock-posy lichens.
A collaborative, open-science team undertook discovery of novel small molecule inhibitors of the SARS-CoV-2 nsp16-nsp10 2'-O-methyltransferase using a high throughput screening approach with the potential to reveal new inhibition strategies. This screen yielded compound 5a, a ligand possessing an electron-deficient double bond, as an inhibitor of SARS-CoV-2 nsp16 activity. Surprisingly, X-ray crystal structures revealed that 5a covalently binds within a previously unrecognized cryptic pocket near the S-adenosylmethionine binding cleft in a manner that prevents occupation by S-adenosylmethionine. Using a multidisciplinary approach, we examined the mechanism of binding of compound 5a to the nsp16 cryptic pocket and developed 5a derivatives that inhibited nsp16 activity and murine hepatitis virus replication in rat lung epithelial cells but proved cytotoxic to cell lines canonically used to examine SARS-CoV-2 infection. Our study reveals the druggability of this newly discovered SARS-CoV-2 nsp16 cryptic pocket, provides novel tool compounds to explore the site, and suggests a new approach for discovery of nsp16 inhibition-based pan-coronavirus therapeutics through structure-guided drug design.
- MeSH
- COVID-19 * MeSH
- krysa rodu rattus MeSH
- methyltransferasy MeSH
- myši MeSH
- S-adenosylmethionin chemie metabolismus MeSH
- SARS-CoV-2 * metabolismus MeSH
- zvířata MeSH
- Check Tag
- krysa rodu rattus MeSH
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
Over time, mountain biota has undergone complex evolutionary histories that have left imprints on its genomic arrangement, geographical distribution and diversity of contemporary lineages. Knowledge on these biogeographical aspects still lags behind for invertebrates inhabiting the Alpine region. In the present study, we examined three scorpion species of the subgenus Euscorpius (Alpiscorpius) from the European Alps using cytogenetic and molecular phylogenetic approaches to determine the variation and population structure of extant lineages at both chromosome and genetic level, and to provide an insight into the species diversification histories. We detected considerable intraspecific variability in chromosome complements and localization of the 18S rDNA loci in all studied species. Such chromosome differences were noticeable as the existence of three [in E. (A.) alpha and E. (A.) germanus] or four [in E. (A.) gamma] range-restricted karyotypic races. These races differed from one another either by 2n [in E. (A.) alpha 2n = 54, 60, 90; in E. (A.) gamma 2n = 58, 60, 88, 86-92], or by the karyotypic formula [in E. (A.) germanus 2n = 34m + 12sm; 36m + 10sm; 42m + 4sm]. Using mitochondrial (16S rRNA, COI) and nuclear (28S rDNA) genetic markers, we examined genetic variation and reconstructed phylogenetic relationships among the karyotypic races. Both approaches provided evidence for the existence of ten deeply divergent lineages exhibiting the features of local endemics and indicating the presence of cryptic species. Molecular dating analyses suggest that these lineages diversified during the Plio-Pleistocene and this process was presumably accompanied by dynamic structural changes in the genome organization.
- MeSH
- alely MeSH
- časové faktory MeSH
- chromozomy genetika MeSH
- druhová specificita MeSH
- fylogeneze MeSH
- genetická variace * MeSH
- genom MeSH
- karyotypizace MeSH
- molekulární evoluce * MeSH
- ribozomální DNA genetika MeSH
- RNA ribozomální 16S genetika MeSH
- štíři genetika MeSH
- zeměpis MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
AIMS: The aim of our study was to scan for cryptic rearrangements using the multiplex ligation probe amplification method in a cohort of 64 probands with mental retardation or developmental delays in combination with at least one of the following symptoms: hypotonia after birth, congenital anomalies, or face dysmorphisms; but without a positive cytogenetic finding. The study contributes to the knowledge of microdeletion syndromes and helps disclose their natural phenotypic variability. RESULTS: In total, 10 positives (16%) were detected, particularly 3 duplications (Xpter-p22.32; 17p11.2; 22q11) and 6 different deletions (1p36; 7q11.23; 10p15; 15q11-q13; 17p11.2; 17p13.3), 1 of these in 2 probands. Besides the well-characterized syndromes, less-often described rearrangements with ambiguous phenotype associations were also detected. CONCLUSIONS: Some rearrangements, particularly duplications, are associated with vague phenotypes; and their frequency could be underestimated.
- MeSH
- chromozomální aberace statistika a číselné údaje MeSH
- chromozomální delece MeSH
- chromozomální poruchy epidemiologie genetika MeSH
- dítě MeSH
- kohortové studie MeSH
- kojenec MeSH
- lidé MeSH
- lidské chromozomy, pár 1 genetika MeSH
- lidské chromozomy, pár 7 MeSH
- mentální retardace epidemiologie genetika MeSH
- mladiství MeSH
- populační genetika MeSH
- Praderův-Williho syndrom epidemiologie genetika MeSH
- předškolní dítě MeSH
- Williamsův-Beurenův syndrom epidemiologie genetika MeSH
- Check Tag
- dítě MeSH
- kojenec MeSH
- lidé MeSH
- mladiství MeSH
- mužské pohlaví MeSH
- předškolní dítě MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Geografické názvy
- Česká republika MeSH
We report the distribution of mosquitoes of the maculipennis complex in two distinct areas of the Czech Republic (Bohemia and South Moravia) and in one locality of neighbouring Slovakia with emphasis on the detection of the newly described cryptic species Anopheles daciae (Linton, Nicolescu & Harbach, 2004). A total of 691 mosquitoes were analysed using a species-specific multiplex PCR assay to differentiate between the members of the maculipennis complex. In the Czech Republic, we found Anopheles maculipennis (with a prevalence rate of 1.4%), Anopheles messeae (49.0%) and Anopheles daciae (49.6%). In Slovakia, only An. messeae (52.1%) and An. daciae (47.9%) were detected. In this study, An. daciae was documented for the first time in the two countries where it represented a markedly higher proportion of maculipennis complex species (with an overall prevalence almost reaching 50%) in comparison to previous reports from Germany, Romania and Poland. The determination of the differential distribution of maculipennis complex species will contribute to assessing risks of mosquito-borne diseases such as malaria or dirofilariasis.
- MeSH
- Anopheles parazitologie MeSH
- Culicidae parazitologie MeSH
- dirofilarióza epidemiologie parazitologie přenos MeSH
- druhová specificita MeSH
- hmyz - vektory parazitologie MeSH
- malárie epidemiologie parazitologie přenos MeSH
- zvířata MeSH
- Check Tag
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Česká republika epidemiologie MeSH
- Slovenská republika epidemiologie MeSH
Mutations in SNRP200 gene cause autosomal-dominant retinal disorder retinitis pigmentosa (RP). The protein product of SNRNP200 is BRR2, a DExD/H box RNA helicase crucial for pre-mRNA splicing. In this study, we prepared p.S1087L and p.R1090L mutations of human BRR2 using bacterial artificial chromosome recombineering and stably expressed them in human cell culture. Mutations in BRR2 did not compromise snRNP assembly and both mutants were incorporated into the spliceosome just as the wild-type (wt) protein. Surprisingly, cells expressing RP mutants exhibited increased splicing efficiency of the LDHA gene. Next, we found that depletion of endogenous BRR2 enhanced usage of a β-globin cryptic splice site while splicing at the correct splice site was inhibited. Proper splicing of optimal and cryptic splice sites was restored in cells expressing BRR2-wt but not in cells expressing RP mutants. Taken together, our data suggest that BRR2 is an important factor in 5'-splice-site recognition and that the RP-linked mutations c.3260C>T (p.S1087L) and c.3269G>T (p.R1090L) affect this BRR2 function.
- MeSH
- alternativní sestřih MeSH
- beta-globiny genetika metabolismus MeSH
- HeLa buňky MeSH
- klonování DNA MeSH
- lidé MeSH
- místa sestřihu RNA genetika MeSH
- mutace * MeSH
- prekurzory RNA genetika metabolismus MeSH
- reportérové geny MeSH
- retinopathia pigmentosa genetika MeSH
- ribonukleoproteiny malé jaderné genetika MeSH
- RNA-helikasy genetika MeSH
- spliceozomy MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
The karyotype of bone-marrow cells at the time of diagnosis is one of the most important prognostic factors in patients with myelodysplastic syndromes (MDS). In some cases, the acquisition of additional genetic aberrations (clonal evolution [CE]) associated with clinical progression may occur during the disease. We analyzed a cohort of 469 MDS patients using a combination of molecular cytogenomic methods to identify cryptic aberrations and to assess their potential role in CE. We confirmed CE in 36 (8%) patients. The analysis of bone-marrow samples with a combination of cytogenomic methods at diagnosis and after CE identified 214 chromosomal aberrations. The early genetic changes in the diagnostic samples were frequently MDS specific (17 MDS-specific/57 early changes). Most progression-related aberrations identified after CE were not MDS specific (131 non-MDS-specific/155 progression-related changes). Copy number neutral loss of heterozygosity (CN-LOH) was detected in 19% of patients. MDS-specific CN-LOH (4q, 17p) was identified in three patients, and probably pathogenic homozygous mutations were found in TET2 (4q24) and TP53 (17p13.1) genes. We observed a statistically significant difference in overall survival (OS) between the groups of patients divided according to their diagnostic cytogenomic findings, with worse OS in the group with complex karyotypes (P = .021). A combination of cytogenomic methods allowed us to detect many cryptic genomic changes and identify genes and genomic regions that may represent therapeutic targets in patients with progressive MDS.
- MeSH
- analýza přežití MeSH
- chromozomální aberace MeSH
- DNA vazebné proteiny genetika MeSH
- dospělí MeSH
- klonální evoluce * MeSH
- lidé středního věku MeSH
- lidé MeSH
- mutace MeSH
- myelodysplastické syndromy klasifikace genetika patologie MeSH
- nádorový supresorový protein p53 genetika MeSH
- prognóza MeSH
- protoonkogenní proteiny genetika MeSH
- senioři nad 80 let MeSH
- senioři MeSH
- ztráta heterozygozity MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- senioři nad 80 let MeSH
- senioři MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
