The beet cyst nematode Heterodera schachtii causes major yield losses in sugar beet. Understanding the interaction between H. schachtii and its host plant is important for developing a sustainable management system. Nematode effectors play a crucial role in initializing and sustaining successful parasitism. In our study, we identified a gene (Hs-Tyr) encoding a tyrosinase functional domain (PF00264). We describe Hs-Tyr as a novel nematode effector. Hs-Tyr is localized in the nematode esophageal gland. Up-regulation of its expression coincided with the parasitic developmental stages of the nematode. Silencing Hs-Tyr by RNA interference made the treated nematodes less virulent. When RNAi-treated nematodes succeeded in infecting the plant, developing females and their associated syncytial nurse cells were significantly smaller than in control plants. Ectopically expressing the Hs-Tyr effector in Arabidopsis increased plant susceptibility to H. schachtii, but not to the root-knot nematode Meloidogyne incognita. Interestingly, Hs-Tyr in the plant promoted plant growth and changed the root architecture. Additionally, the expression of Hs-Tyr in Arabidopsis caused changes in the homeostasis of several plant hormones especially auxin and the ethylene precursor aminocyclopropane-carboxylic acid.
- MeSH
- Arabidopsis metabolismus parazitologie MeSH
- ezofágus metabolismus MeSH
- hlístice metabolismus patogenita MeSH
- interakce hostitele a parazita * MeSH
- proteiny červů genetika metabolismus MeSH
- regulátory růstu rostlin metabolismus MeSH
- tyrosinasa genetika metabolismus MeSH
- virulence MeSH
- zvířata MeSH
- Check Tag
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Počas gastroezofágového refluxu (GER) dochádza k výraznému poklesu pH v lumen pažeráka. V úrovniach nervových zakončení sliznice pažeráka je ale vďaka jej bariérovej funkcii pH oveľa vyššie (pH 5,5–6,5). Napriek tomu, že bariérová funkcia sliznice je pri pažerákovej refluxovej chorobe (GERD) čiastočne porušená, dostatočne zabraňuje difúzii kyseliny do tkaniva a nedochádza k následnej deštrukcii buniek. Predpokladá sa, že pažerákové nociceptívne neuróny, ktoré sprostredkujú bolesť a pyrózu, exprimujú receptory vysoko senzitívne na kyselinu, a sú teda stimulované už pri miernom poklese pH. V recentných modelových štúdiách na morčatách sme dokázali, že už slabá kyselina (pH 5,5–6,5) môže masívne stimulovať spinálne nociceptívne C-vlákna. V súlade s týmto pozorovaním sme pomocou génovej analýzy zistili, že pažerákové aferentné nervové vlákna redundantne exprimujú viaceré receptory, ktoré sú vysoko citlivé na kyselinu. Identifikovali sme iónové kanály citlivé na kyselinu (ASICs – acid sensing ion channels), receptory spriahnuté s G-proteínom reagujúce na kyselinu (OGR1 – proton sensing G-protein coupled receptor) a TASK1 zo skupiny drasíkových kanálov zo skupiny K2P. Vysoká vnímavosť nociceptívnych nervov na kyselinu pri oslabenej báriérovej funkcii sliznice (napr. pri GERD) prispieva k vzniku ezofágových senzácií, ako je pyróza a bolesť pažerákového pôvodu. Receptory, ktoré sprostredkúvajú citlivosť na kyselinu, môžu v budúcnosti slúžiť ako nové terapeutické ciele pre aditívnu alebo alternatívnu liečbu k antisekrečnej liečbe.
The pH in the esophageal lumen can be very low (pH 1) during acidic reflux. However, the pH in the esophageal mucosa where the esophageal afferent nerves terminate is predicted to be much higher (pH 5.5–6.5). This is because the esophageal mucosal barrier, even when reduced in gastroesophageal reflux disease, still prevents most acid from diffusing into the esophageal tissue and causing widespread cellular death. It has therefore been predicted that the esophageal nociceptive (pain- and heartburn-mediating) nerves are stimulated by modest acid (pH 5.5–6.5) and express highly sensitive acid receptors. Recent studies in a guinea pig model demonstrated that weak acid (pH 5.5–6.5) robustly stimulates esophageal spinal nociceptive C-fibers. Consistent with this observation, gene expression analysis revealed that esophageal C-fibers redundantly express multiple acid sensing ion channels (ASICs), proton-sensing G-protein coupled receptor OGR1, and the highly acid sensitive two-pore-domain (K2P) TASK1-family potassium channel. The high acid sensitivity of esophageal nociceptive nerves contributes to heartburn and pain in conditions of reduced mucosal barrier function (e. g. GERD), suggesting that the receptors mediating this high acid sensitivity could be targeted by novel drugs as a combinatorial therapy with, or an alternative to acid suppression.
- MeSH
- aferentní nervové dráhy MeSH
- ezofágus * inervace metabolismus MeSH
- gastroezofageální reflux * patofyziologie MeSH
- iontové kanály ASIC * MeSH
- kationtové kanály TRPV MeSH
- koncentrace vodíkových iontů MeSH
- lidé MeSH
- neurony aferentní MeSH
- nociceptory MeSH
- pyróza patofyziologie MeSH
- sliznice jícnu inervace MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- práce podpořená grantem MeSH
- přehledy MeSH
Esophageal adenocarcinoma (EAC) is highly aggressive malignancy that frequently develops from Barrett's esophagus (BE), a premalignant pathologic change occurring in the lower end of the esophagus. MicroRNAs (miRNAs) are small, non-coding RNAs that function as posttranscriptional regulators of gene expression and were repeatedly proved to play key roles in pathogenesis of BE as well as EAC. In our study, we used Affymetrix GeneChip miRNA arrays to obtain miRNA expression profiles in total of 119 tissue samples [24 normal esophageal mucosa (EM), 60 BE and 35 EAC]. We identified a number of miRNAs, that showed altered expression progressively in sequence EM, BE and EAC, including for instance miR-21, miR-25, miR-194 and miR-196a with increasing levels (P < 0.0015) and miR-203, miR-205, miR-210 and miR-378 with decreasing levels (P < 0.0001). The subsequent analysis revealed four diagnostic miRNA signatures enabling to distinguish EM and BE [12 miRNAs, area under curve (AUC) = 0.971], EM and EAC (13 miRNAs, AUC = 1.0), BE without and BE with dysplasia (21 miRNAs, AUC = 0.856) and BE without dysplastic changes and BE with dysplasia together with EAC (2 miRNAs, AUC = 0.886). We suggest that miRNA expression profiling expands current knowledge in molecular pathology of Barrett's-based carcinogenesis and enables identification of molecular biomarkers for early detection of BE dysplasia and progression to EAC.
- MeSH
- adenokarcinom genetika patologie MeSH
- Barrettův syndrom genetika patologie MeSH
- ezofágus metabolismus patologie MeSH
- lidé středního věku MeSH
- lidé MeSH
- lymfatické metastázy MeSH
- mikro RNA genetika MeSH
- nádorové biomarkery genetika MeSH
- nádory jícnu genetika patologie MeSH
- následné studie MeSH
- prognóza MeSH
- progrese nemoci MeSH
- regulace genové exprese u nádorů MeSH
- retrospektivní studie MeSH
- ROC křivka MeSH
- sekvenční analýza hybridizací s uspořádaným souborem oligonukleotidů MeSH
- senioři MeSH
- staging nádorů MeSH
- stanovení celkové genové exprese * MeSH
- studie případů a kontrol MeSH
- Check Tag
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- senioři MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- klinické zkoušky MeSH
- práce podpořená grantem MeSH
- srovnávací studie MeSH
- MeSH
- Barrettův syndrom metabolismus patologie MeSH
- ezofágus metabolismus patologie MeSH
- finanční podpora výzkumu jako téma MeSH
- gastroezofageální junkce metabolismus patologie MeSH
- imunoenzymatické techniky MeSH
- keratiny metabolismus MeSH
- lidé MeSH
- žaludeční sliznice metabolismus patologie MeSH
- Check Tag
- lidé MeSH
BACKGROUND: The oesophageal epithelium is exposed routinely to noxious agents in the environment, including gastric acid, thermal stress, and chemical toxins. These epithelial cells have presumably evolved effective protective mechanisms to withstand tissue damage and repair injured cells. Heat shock protein or stress protein responses play a central role in protecting distinct cell types from different types of injury. AIM: To determine (i) whether biochemical analysis of stress protein responses in pinch biopsy specimens from human oesophageal epithelium is feasible; (ii) whether undue stresses are imposed on cells by the act of sample collection, thus precluding analysis of stress responses; and (iii) if amenable to experimentation, the type of heat shock protein (Hsp) response that operates in the human oesophageal epithelium. METHODS: Tissue from the human oesophagus comprised predominantly of squamous epithelium was acquired within two hours of biopsy and subjected to an in vitro heat shock. Soluble tissue cell lysates derived from untreated or heat shocked samples were examined using denaturing polyacrylamide gel electrophoresis for changes in: (i) the pattern of general protein synthesis by labelling epithelial cells with 35S-methionine and (ii) the levels of soluble Hsp70 protein and related isoforms using immunochemical protein blots. RESULTS: A single pinch biopsy specimen is sufficient to extract and analyse specific sets of polypeptides in the oesophageal epithelium. After ex vivo heat shock, a classic inhibition of general protein synthesis is observed and correlates with the increased synthesis of two major proteins of molecular weight of 60 and 70 kDa. Notably, cells from unheated controls exhibit a "stressed" biochemical state 22 hours after incubation at 37 degrees C, as shown by inhibition of general protein synthesis and increased synthesis of the 70 kDa protein. These data indicate that only freshly acquired specimens are suitable for studying stress responses ex vivo. No evidence was found that the two heat induced polypeptides are previously identified Hsp70 isoforms. In fact, heat shock results in a reduction in the steady state concentrations of Hsp70 protein in the oesophageal epithelium. CONCLUSION: Systematic and highly controlled studies on protein biochemistry are possible on epithelial biopsy specimens from the human oesophagus. These technical innovations have permitted the discovery of a novel heat shock response operating in the oesophageal epithelium. Notably, two polypeptides were synthesised after heat shock that seem to differ from Hsp70 protein. In addition, the striking reduction in steady state concentrations of Hsp70 protein after heat shock suggests that oesophageal epithelium has evolved an atypical biochemical response to thermal stress.
- MeSH
- biopsie MeSH
- elektroforéza v polyakrylamidovém gelu MeSH
- epitel metabolismus MeSH
- ezofágus chemie metabolismus MeSH
- lidé MeSH
- proteiny tepelného šoku HSP70 * analýza MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- práce podpořená grantem MeSH
