Filamentation
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Given the role of intermediate filaments (IFs) in normal cell physiology and scores of IF-linked diseases, the importance of understanding their molecular structure is beyond doubt. Research into the IF structure was initiated more than 30 years ago, and some important advances have been made. Using crystallography and other methods, the central coiled-coil domain of the elementary dimer and also the structural basis of the soluble tetramer formation have been studied to atomic precision. However, the molecular interactions driving later stages of the filament assembly are still not fully understood. For cytoplasmic IFs, much of the currently available insight is due to chemical cross-linking experiments that date back to the 1990s. This technique has since been radically improved, and several groups have utilized it recently to obtain data on lamin filament assembly. Here, we will summarize these findings and reflect on the remaining open questions and challenges of IF structure. We argue that, in addition to X-ray crystallography, chemical cross-linking and cryoelectron microscopy are the techniques that should enable major new advances in the field in the near future.
- MeSH
- cytoskelet chemie metabolismus MeSH
- fyziologie buňky * MeSH
- intermediární filamenta chemie metabolismus MeSH
- lidé MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- přehledy MeSH
Candida albicans is the most common human fungal pathogen and can grow as yeast or filaments, depending on the environmental conditions. The filamentous form is of particular interest because it can play a direct role in adherence and pathogenicity. Therefore, the purpose of this study was to evaluate the effects of three clinical strains of Lactobacillus on C. albicans filamentation as well as their probiotic potential in pathogen-host interactions via an experimental candidiasis model study in Galleria mellonella. We used the reference strain Candida albicans ATCC 18804 and three clinical strains of Lactobacillus: L. rhamnosus strain 5.2, L. paracasei strain 20.3, and L. fermentum strain 20.4. First, the capacity of C. albicans to form hyphae was tested in vitro through association with the Lactobacillus strains. After that, we verified the ability of these strains to attenuate experimental candidiasis in a Galleria mellonella model through a survival curve assay. Regarding the filamentation assay, a significant reduction in hyphae formation of up to 57% was observed when C. albicans was incubated in the presence of the Lactobacillus strains, compared to a control group composed of only C. albicans. In addition, when the larvae were pretreated with Lactobacillus spp. prior to C. albicans infection, the survival rate of G. mellonela increased in all experimental groups. We concluded that Lactobacillus influences the growth and expression C. albicans virulence factors, which may interfere with the pathogenicity of these microorganisms.
- MeSH
- analýza přežití MeSH
- antibióza MeSH
- Candida albicans účinky léků růst a vývoj MeSH
- hyfy účinky léků MeSH
- kandidóza prevence a kontrola MeSH
- Lactobacillus fyziologie MeSH
- larva mikrobiologie MeSH
- modely nemocí na zvířatech MeSH
- můry mikrobiologie MeSH
- probiotika farmakologie MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
Pathogenicity of Candida albicans is associated with its capacity switch from yeast-like to hyphal growth. The hyphal form is capable to penetrate the epithelial surfaces and to damage the host tissues. Therefore, many investigations have focused on mechanisms that control the morphological transitions of C. albicans. Recently, certain studies have showed that non-albicans Candida species can reduce the capacity of C. albicans to form biofilms and to develop candidiasis in animal models. Then, the objective of this study was to evaluate the effects of Candida krusei and Candida glabrata on the morphogenesis of C. albicans. Firstly, the capacity of reference and clinical strains of C. albicans in forming hyphae was tested in vitro. After that, the expression of HWP1 (hyphal wall protein 1) gene was determined by quantitative real-time PCR (polymerase chain reaction) assay. For both reference and clinical strains, a significant inhibition of the hyphae formation was observed when C. albicans was incubated in the presence of C. krusei or C. glabrata compared to the control group composed only by C. albicans. In addition, the culture mixed of C. albicans-C. krusei or C. albicans-C. glabrata reduced significantly the expression of HWP1 gene of C. albicans in relation to single cultures of this specie. In both filamentation and gene expression assays, C. krusei showed the higher inhibitory activity on the morphogenesis of C. albicans compared to C. glabrata. C. krusei and C. glabrata are capable to reduce the filamentation of C. albicans and consequently decrease the expression of the HWP1 gene.
- MeSH
- Candida albicans genetika růst a vývoj metabolismus MeSH
- Candida glabrata fyziologie MeSH
- Candida fyziologie MeSH
- down regulace MeSH
- fungální proteiny genetika metabolismus MeSH
- hyfy genetika růst a vývoj metabolismus MeSH
- lidé MeSH
- membránové glykoproteiny genetika metabolismus MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
Journal of applied bacteriology ; suppl. to vol. 67 Society for Applied Microbiology symposium series, ISSN 0267-4440 no. 18
iiiS, 149 s. : obr., tab. ; 24 cm
- MeSH
- Aspergillus MeSH
- Fusarium MeSH
- houby MeSH
- Penicillium MeSH
- potravinářská mikrobiologie MeSH
- Publikační typ
- kongresy MeSH
- MeSH
- biofilmy * MeSH
- houby * MeSH
- lidé MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- práce podpořená grantem MeSH
Our previous findings performed in rat tissues demonstrated that intermediate filament nestin is expressed in endothelial cells of newly formed blood vessels of developing organs and neural transplants. The aim of the present study was to identify other cellular markers expressed in nestin-positive (nestin+) blood vessels. To reach this goal we performed double immunofluorescent study to co-localize nestin with endothelium-specific markers (CD31, CD34 II, vimentin) or markers of perivascular cells (GFAP, SMA) in paraffin-embedded sections of normal human brain tissue, low- and high-grade gliomas, postinfarcted heart and samples of non-neural tumours. Our findings documented that all the samples examined contained blood vessels with different ratio of nestin+ endothelial cells. Double immunostaining provided unambiguous evidence that endothelial cells expressed nestin and allowed them to distinguish from other nestin+ elements (perivascular astrocytic endfeet, undifferentiated tumour cells, smooth muscle cells and pericytes). Nestin+ endothelium was not confined only to newly formed capillaries but was also observed in blood vessels of larger calibres, frequently in arterioles and venules. We conclude that nestin represents a reliable vascular marker that is expressed in endothelial cells. Elevation of nestin expression likely corresponds to reorganization of intermediate filament network in the cytoskeleton of endothelial cells in the course of their maturation or adaptation to changes in growing tissues.
- MeSH
- aktiny analýza MeSH
- antigeny CD31 analýza MeSH
- antigeny CD34 analýza MeSH
- cévní endotel chemie metabolismus MeSH
- cévy metabolismus MeSH
- financování organizované MeSH
- gliový fibrilární kyselý protein analýza MeSH
- imunohistochemie MeSH
- koronární cévy metabolismus MeSH
- lidé MeSH
- mozek krevní zásobení MeSH
- nádory mozku krevní zásobení MeSH
- nádory metabolismus MeSH
- proteiny intermediálních filament metabolismus MeSH
- proteiny nervové tkáně metabolismus MeSH
- vimentin metabolismus MeSH
- Check Tag
- lidé MeSH
Nestin je jedno z intermediárních filament exprimovaných v proliferujících neuronálních proge- nitorových buňkách CNS a PNS (centrálního a periferního nervového systému). Jeho postnatální reexprese se objevuje zejména u nádorů CNS a koreluje s vysokým stupněm malignity. Naše studie je zaměřena na sledování exprese nestinu u benigních a maligních kožních melanocytárních lézí, s cílem zjistit prognostický význam tohoto proteinu. Vyšetřili jsme 127 bioptických vzorků, z nichž bylo 42 nodulárních melanomů (NM), 32 superficiálních melanomů (SSM), 10 dysplastických névů (DN) a 43 běžných intradermálních i dermoepidermálních pigmentových névů. Prokázali jsme vý- znamné zvýšení exprese nestinu u jednotlivých typů melanomů, zejména u melanomů nodulárních. Protein byl lokalizován zvláště v periferních, invazivních částech tumoru. Závěr: Sledování nesti- nu by mohlo být důležitým doplňkem ostatních melanomových markerů.
Nestin is one of intermedial filaments exprimed in proliferating progenitor cells of the CNS and PNS (central and peripheral nervous system). Postnatal reexpression of the protein occures main- ly in CNS tumors and correlates with a high grade of malignancy. The aim of our study is assess- ment of the nestin expression in benign and malignant skin melanocytic lesions with respect to presume a prognostic role of this protein. We examined 127 bioptic specimens, including 42 nodu- lar melanomas (NM), 32 superficial spreading melanomas (SSM), 10 dysplastic nevi and 43 common intradermal or dermoepidermal nevi. We proved significant increase in nestin expression in mela- noma groups, especially in nodular melanomas, where nestin was localized mainly in the periphe- ral, invasive areas of the tumor mass. Conclusion: Detection of nestin expression might be used as an additional melanocytic tumour marker.
