排序方式: 共有56条查询结果,搜索用时 15 毫秒
41.
Pax-Six-Eya-Dach network during amphioxus development: conservation in vitro but context specificity in vivo 总被引:3,自引:0,他引:3
Kozmik Z Holland ND Kreslova J Oliveri D Schubert M Jonasova K Holland LZ Pestarino M Benes V Candiani S 《Developmental biology》2007,306(1):143-159
The Drosophila retinal determination gene network occurs in animals generally as a Pax-Six-Eyes absent-Dachshund network (PSEDN). For amphioxus, we describe the complete network of nine PSEDN genes, four of which-AmphiSix1/2, AmphiSix4/5, AmphSix3/6, and AmphiEya-are characterized here for the first time. For amphioxus, in vitro interactions among the genes and proteins of the network resemble those of other animals, except for the absence of Dach-Eya binding. Amphioxus PSEDN genes are expressed in highly stage- and tissue-specific patterns (sometimes conspicuously correlated with the local intensity of cell proliferation) in the gastrular organizer, notochord, somites, anterior central nervous system, peripheral nervous system, pharyngeal endoderm, and the likely homolog of the vertebrate adenohypophysis. In this last tissue, the anterior region expresses all three amphioxus Six genes and is a zone of active cell proliferation, while the posterior region expresses only AmphiPax6 and is non-proliferative. In summary, the topologies of animal PSEDNs, although considerably more variable than originally proposed, are conserved enough to be recognizable among species and among developing tissues; this conservation may reflect indispensable involvement of PSEDNs during the critically important early phases of embryology (e.g. in the control of mitosis, apoptosis, and cell/tissue motility). 相似文献
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OBJECTIVE: To evaluate the number of micronuclei in snake-like chromatin (SLC) cells in the conjunctival epithelium of keratoconjunctivitis sicca (KCS) patients. To elucidate possible correlations between SLC cell numbers and KCS intensity. STUDY DESIGN: Impression cytology specimens from the bulbar conjunctiva of healthy controls and KCS patients were harvested and divided into 3 groups: group 1, controls; group 2, KCS SLC-negative; and group 3, KCS SLC-positive. The number of micronuclei (MNi) in SLC-negative and SLC-positive epithelial cells of each group was counted. RESULTS: The number of MNi in SLC-negative cells of groups 1 and 2 did not exceed 1 MNi/1,000 cells. A significant increase in the frequency of micronuclei in the upper bulbar conjunctiva was noted in SLC-positive (14.75 +/- 8.09 MNi/1,000 cells) as well as SLC-negative cells (4.0 +/- 3.83 MNi/1,000 cells) of group 3. CONCLUSION: We demonstrate here that the presence of MNi in the conjunctival epithelium of KCS patients could be a characteristic feature accompanying SLC cells. The fact that increased numbers of SLC cells correlates with impaired values in clinical test as well as decreased goblet and epithelial cell densities confirms that the presence of SLC cells correlates with KCS intensity. 相似文献
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Jarmila Kralova Nataliia Pavliuchenko Matej Fabisik Kristyna Ilievova Frantisek Spoutil Jan Prochazka Jana Pokorna Radislav Sedlacek Tomas Brdicka 《The Journal of biological chemistry》2021,297(4)
A number of human autoinflammatory diseases manifest with severe inflammatory bone destruction. Mouse models of these diseases represent valuable tools that help us to understand molecular mechanisms triggering this bone autoinflammation. The Pstpip2cmo mouse strain is among the best characterized of these; it harbors a mutation resulting in the loss of adaptor protein PSTPIP2 and development of autoinflammatory osteomyelitis. In Pstpip2cmo mice, overproduction of interleukin-1β (IL-1β) and reactive oxygen species by neutrophil granulocytes leads to spontaneous inflammation of the bones and surrounding soft tissues. However, the upstream signaling events leading to this overproduction are poorly characterized. Here, we show that Pstpip2cmo mice deficient in major regulator of Src-family kinases (SFKs) receptor-type protein tyrosine phosphatase CD45 display delayed onset and lower severity of the disease, while the development of autoinflammation is not affected by deficiencies in Toll-like receptor signaling. Our data also show deregulation of pro-IL-1β production by Pstpip2cmo neutrophils that are attenuated by CD45 deficiency. These data suggest a role for SFKs in autoinflammation. Together with previously published work on the involvement of protein tyrosine kinase spleen tyrosine kinase, they point to the role of receptors containing immunoreceptor tyrosine-based activation motifs, which after phosphorylation by SFKs recruit spleen tyrosine kinase for further signal propagation. We propose that this class of receptors triggers the events resulting in increased pro-IL-1β synthesis and disease initiation and/or progression. 相似文献
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Brestic Marian Zivcak Marek Kunderlikova Kristyna Sytar Oksana Shao Hongbo Kalaji Hazem M. Allakhverdiev Suleyman I. 《Photosynthesis research》2015,125(1-2):151-166
Photosynthesis Research - In vivo analyses of electron and proton transport-related processes as well as photoprotective responses were carried out at different stages of growth in chlorophyll b... 相似文献
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The Czech Republic has one of the highest incidences of colorectal cancer (CRC) in Europe. To evaluate whether sporadic CRCs in Czech patients have specific mutational profiles we analysed somatic genetic changes in known CRC genes (APC, KRAS, TP53, CTNNB1, MUTYH and BRAF, loss of heterozygosity (LOH) at the APC locus, microsatellite instability (MSI), and methylation of the MLH1 promoter) in 103 tumours from 102 individuals. The most frequently mutated gene was APC (68.9% of tumours), followed by KRAS (31.1%), TP53 (27.2%), BRAF (8.7%) and CTNNB1 (1.9%). Heterozygous germline MUTYH mutations in 2 patients were unlikely to contribute to the development of their CRCs. LOH at the APC locus was found in 34.3% of tumours, MSI in 24.3% and MLH1 methylation in 12.7%. Seven tumours (6.9%) were without any changes in the genes tested. The analysis yielded several findings possibly specific for the Czech cohort. Somatic APC mutations did not cluster in the mutation cluster region (MCR). Tumours with MSI but no MLH1 methylation showed earlier onset and more severe mutational profiles compared to MSI tumours with MLH1 methylation. TP53 mutations were predominantly located outside the hot spots, and transitions were underrepresented. Our analysis supports the observation that germline MUTYH mutations are rare in Czech individuals with sporadic CRCs. Our findings suggest the influence of specific ethnic genetic factors and/or lifestyle and dietary habits typical for the Czech population on the development of these cancers. 相似文献
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Anastasia Felker Susan Nieuwenhuize Aymeric Dolbois Kristyna Blazkova Christopher Hess Larry W. L. Low Sibylle Burger Natasha Samson Tom J. Carney Petr Bartunek Cristina Nevado Christian Mosimann 《PloS one》2016,11(4)
Mutant Estrogen Receptor (ERT2) ligand-binding domain fusions with Cre recombinase are a key tool for spatio-temporally controlled genetic recombination with the Cre/lox system. CreERT2 is efficiently activated in a concentration-dependent manner by the Tamoxifen metabolite trans-4-OH-Tamoxifen (trans-4-OHT). Reproducible and efficient Cre/lox experimentation is hindered by the gradual loss of CreERT2 induction potency upon prolonged storage of dissolved trans-4-OHT, which potentially results from gradual trans-to-cis isomerization or degradation. Here, we combined zebrafish CreERT2 recombination experiments and cell culture assays to document the gradual activity loss of trans-4-OHT and describe the alternative Tamoxifen metabolite Endoxifen as more stable alternative compound. Endoxifen retains potent activation upon prolonged storage (3 months), yet consistently induces half the ERT2 domain fusion activity compared to fresh trans-4-OHT. Using 1H-NMR analysis, we reveal that trans-4-OHT isomerization is undetectable upon prolonged storage in either DMSO or Ethanol, ruling out isomer transformation as cause for the gradual loss of trans-4-OHT activity. We further establish that both trans-4-OHT and Endoxifen are insensitive to light exposure under regular laboratory handling conditions. We attribute the gradual loss of trans-4-OHT potency to precipitation over time, and show that heating of aged trans-4-OHT aliquots reinstates their CreERT2 induction potential. Our data establish Endoxifen as potent and reproducible complementary compound to 4-OHT to control ERT2 domain fusion proteins in vivo, and provide a framework for efficient chemically controlled recombination experiments. 相似文献
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Martin Rossmeisl Tomas Jelenik Zuzana Jilkova Kristyna Slamova Vladimir Kus Michal Hensler Dasa Medrikova Ctibor Povysil Pavel Flachs Vidya Mohamed‐Ali Morten Bryhn Kjetil Berge Anne K. Holmeide Jan Kopecky 《Obesity (Silver Spring, Md.)》2009,17(5):1023-1031
The n‐3 polyunsaturated fatty acids, especially eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), exert hypolipidemic effects and prevent development of obesity and insulin resistance in animals fed high‐fat diets. We sought to determine the efficacy of α‐substituted DHA derivatives as lipid‐lowering, antiobesity, and antidiabetic agents. C57BL/6 mice were given a corn oil‐based high‐fat (35% weight/weight) diet (cHF), or cHF with 1.5% of lipids replaced with α‐methyl DHA ethyl ester (Substance 1), α‐ethyl DHA ethyl ester (Substance 2), α,α‐di‐methyl DHA ethyl ester (Substance 3), or α‐thioethyl DHA ethyl ester (Substance 4) for 4 months. Plasma markers of glucose and lipid metabolism, glucose tolerance, morphology, tissue lipid content, and gene regulation were characterized. The cHF induced obesity, hyperlipidemia, impairment of glucose homeostasis, and adipose tissue inflammation. Except for Substance 3, all other substances prevented weight gain and Substance 2 exerted the strongest effect (63% of cHF‐controls). Glucose intolerance was significantly prevented (~67% of cHF) by both Substance 1 and Substance 2. Moreover, Substance 2 lowered fasting glycemia, plasma insulin, triacylglycerols, and nonesterified fatty acids (73, 9, 47, and 81% of cHF‐controls, respectively). Substance 2 reduced accumulation of lipids in liver and skeletal muscle, as well as adipose tissue inflammation associated with obesity. Substance 2 also induced weight loss in dietary obese mice. In contrast to DHA administered either alone or as a component of the EPA/DHA concentrate (replacing 15% of dietary lipids), Substance 2 also reversed established glucose intolerance in obese mice. Thus, Substance 2 represents a novel compound with a promising potential in the treatment of obesity and associated metabolic disturbances. 相似文献
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Kristyna Brabnikova-Maresova Katerina Jarosova Karel Pavelka Jan J Stepan 《Arthritis research & therapy》2014,16(5)