Telomere deregulation is a hallmark of cancer. Telomere length measured in lymphocytes (LTL) has been shown to be a risk marker for several cancers. For pancreatic ductal adenocarcinoma (PDAC) consensus is lacking whether risk is associated with long or short telomeres. Mendelian randomization approaches have shown that a score built from SNPs associated with LTL could be used as a robust risk marker. We explored this approach in a large scale study within the PANcreatic Disease ReseArch (PANDoRA) consortium. We analyzed 10 SNPs (ZNF676-rs409627, TERT-rs2736100, CTC1-rs3027234, DHX35-rs6028466, PXK-rs6772228, NAF1-rs7675998, ZNF208-rs8105767, OBFC1-rs9420907, ACYP2-rs11125529 and TERC-rs10936599) alone and combined in a LTL genetic score ("teloscore", which explains 2.2% of the telomere variability) in relation to PDAC risk in 2,374 cases and 4,326 controls. We identified several associations with PDAC risk, among which the strongest were with the TERT-rs2736100 SNP (OR = 1.54; 95%CI 1.35-1.76; p = 1.54 × 10-10 ) and a novel one with the NAF1-rs7675998 SNP (OR = 0.80; 95%CI 0.73-0.88; p = 1.87 × 10-6 , ptrend = 3.27 × 10-7 ). The association of short LTL, measured by the teloscore, with PDAC risk reached genome-wide significance (p = 2.98 × 10-9 for highest vs. lowest quintile; p = 1.82 × 10-10 as a continuous variable). In conclusion, we present a novel genome-wide candidate SNP for PDAC risk (TERT-rs2736100), a completely new signal (NAF1-rs7675998) approaching genome-wide significance and we report a strong association between the teloscore and risk of pancreatic cancer, suggesting that telomeres are a potential risk factor for pancreatic cancer.

• MeSH
• celogenomová asociační studie MeSH
• duktální karcinom pankreatu genetika   MeSH
• jednonukleotidový polymorfismus MeSH
• lidé středního věku MeSH
• lidé MeSH
• lymfocyty metabolismus   MeSH
• nádory slinivky břišní genetika   MeSH
• ribonukleoproteiny genetika   MeSH
• senioři MeSH
• studie případů a kontrol MeSH
• telomerasa genetika   metabolismus   MeSH
• telomery metabolismus   MeSH
• zkracování telomer genetika   MeSH
• Check Tag
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Geografické názvy
• Evropa MeSH

Reproduction success in angiosperm plants depends on robust pollen tube growth through the female pistil tissues to ensure successful fertilization. Accordingly, there is an apparent evolutionary trend to accumulate significant reserves during pollen maturation, including a population of stored mRNAs, that are utilized later for a massive translation of various proteins in growing pollen tubes. Here, we performed a thorough transcriptomic and proteomic analysis of stored and translated transcripts in three subcellular compartments of tobacco (Nicotiana tabacum), long-term storage EDTA/puromycin-resistant particles, translating polysomes, and free ribonuclear particles, throughout tobacco pollen development and in in vitro-growing pollen tubes. We demonstrated that the composition of the aforementioned complexes is not rigid and that numerous transcripts were redistributed among these complexes during pollen development, which may represent an important mechanism of translational regulation. Therefore, we defined the pollen sequestrome as a distinct and highly dynamic compartment for the storage of stable, translationally repressed transcripts and demonstrated its dynamics. We propose that EDTA/puromycin-resistant particle complexes represent aggregated nontranslating monosomes as the primary mediators of messenger RNA sequestration. Such organization is extremely useful in fast tip-growing pollen tubes, where rapid and orchestrated protein synthesis must take place in specific regions.

• MeSH
• polyribozomy genetika   metabolismus   MeSH
• proteom genetika   metabolismus   MeSH
• proteomika metody   MeSH
• pyl genetika   růst a vývoj   metabolismus   MeSH
• pylová láčka genetika   růst a vývoj   metabolismus   MeSH
• regulace genové exprese u rostlin MeSH
• ribonukleoproteiny genetika   metabolismus   MeSH
• ribozomy genetika   metabolismus   MeSH
• rostlinné proteiny genetika   metabolismus   MeSH
• stanovení celkové genové exprese metody   MeSH
• tabák genetika   růst a vývoj   metabolismus   MeSH
• vývojová regulace genové exprese MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

• MeSH
• cytoplazmatická granula * genetika   metabolismus   MeSH
• fyziologie buňky fyziologie   genetika   MeSH
• posttranslační úpravy proteinů MeSH
• reakce na tepelný šok * fyziologie   genetika   MeSH
• ribonukleoproteiny genetika   metabolismus   MeSH
• Saccharomyces cerevisiae * fyziologie   genetika   metabolismus   MeSH
• signální dráha UPR MeSH

Histologically verified pairs (n=10) of pancreatic tumors and non-neoplastic tissues were used for quantitative real-time PCR and the stability of 24 reference genes was analyzed with geNorm and NormFinder software. Raw C{q} values correlated with the degree of RNA degradation. This correlation was abolished by normalization to C{q} of 18S endogenous control gene. Both geNorm and NormFinder programs suggested EIF2B1, ELF1, MRPL19, and POP4 as the same most stable genes. We have thus identified suitable reference genes for future expression studies in pancreatic carcinoma. Normalization method reducing the effects of RNA degradation on the quality of results was also developed.

• MeSH
• eukaryotický iniciační faktor 2B genetika   MeSH
• exprese genu MeSH
• jaderné proteiny genetika   MeSH
• karcinom diagnóza   genetika   patologie   MeSH
• kvantitativní polymerázová řetězová reakce MeSH
• lidé středního věku MeSH
• lidé MeSH
• mitochondriální proteiny genetika   MeSH
• nádorové biomarkery genetika   MeSH
• nádory slinivky břišní diagnóza   genetika   patologie   MeSH
• pankreas metabolismus   patologie   MeSH
• ribonukleasy genetika   MeSH
• ribonukleoproteiny genetika   MeSH
• ribozomální proteiny genetika   MeSH
• senioři MeSH
• software MeSH
• stabilita RNA MeSH
• stanovení celkové genové exprese MeSH
• transkripční faktory genetika   MeSH
• Check Tag
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Vývoj patologického fenotypu u pacientů s myotonickou dystrofií závisí značnou měrou na toxickém účinku transkriptu expandované repetice genu DMPK a jeho interakci s vazebnými proteiny. Vztah mezi CUGexp tohoto genu a vazebnými proteiny MBNL1 a MBNL2 byl dosud studován na tkáňových kulturách myoblastů a na transgenních zvířatech. V tomto sdělení podáváme první molekulárně genetickou analýzu fetálních tkání plodu z rodiny postižené myotonickou dystrofií prvního typu (MD1). Intrauterinní vývoj, zrání a diferenciace kosterního svalstva plodu (360 g, 22. týden) byly jen mírně opožděny. Paternálně zděděná expanze repetice CTG v genu DMPK (350 CTG) byla potvrzena molekulárně genetickou analýzou a následné histopatologické vyšetření plodu prokázalo znaky myotonické dystrofie. Tkáně získané autopsií (kosterní sval, jícen, žaludek a střevo) byly vyšetřeny histologickými i molekulárně genetickými (imunohistochemickou analýzou proteinů MBNL1 a MBNL2, a in situ hybridizací DMPK CUGexp) metodami. Intranukleární ložiska (foci) s CUG transkripty byla zjištěna v kosterním svalu, ve svalovině (muscularis externa) zažívací trubice, v cévní medii, endotelu a intramurálních nervových pleteních i v epitelu. Protein MBNL1 přitom s ložisky expandovaných transkriptů extenzivně kolokalizoval ve všech tkáních. Naproti tomu byl protein MBNL2 nalezen též v cytoplazmě. Přítomnost transkriptu DMPK s expandovanou repeticí CUG a proteinu MBNL1 v intranukleárních fokusech fetálních tkání MD1 pacientů může teoreticky znamenat sekvestraci proteinu MBNL1, a tak přispět ke generaci patologického fenotypu MD1.

Development of the pathological phenotype in patients with myotonic dystrophy (MD1) largely depends on toxic effects of expanded DMPK gene repeats (CUGexp) transcription and their interaction with binding proteins. The relationship between DMPK CUGexp, MBNL1 and MBNL2 has so far been studied on tissue cultures (myoblast cell lines) and transgenic animals. In this report, the first in situ molecular genetic analysis of fetal tissue from a family affected by MD1 is presented. Intrauterine development, maturation and differentiation of skeletal muscles of the fetus (360 g, 22nd week of pregnancy) were only slightly delayed. In the fetus, paternally inherited expansion of the CTG repeat in the DMPK gene (350 CTG) was confirmed by molecular analysis. Subsequent histopathological examination revealed signs of myotonic dystrophy. Fetal tissue obtained at autopsy (skeletal muscles, esophagus, stomach and intestines), were studied by histopathological, immunofluorescence (expression of MBNL1/MBNL2 proteins) and in situ hybridization (DMPK CUGexp) methods. Intranuclear CUGexp-containing foci were present in skeletal muscle fibers, muscularis externa of the esophagus, stomach and intestines, vascular smooth muscle, neurons and Schwann cells of intrinsic ganglionic plexuses, and epithelial cells. MBNL1 protein was largely co-localized with the CUGexp foci in all tissues examined. Contrarily, MBNL2 protein was also detected in the tissue cytoplasm. The presence of DMPK transcript with expanded CUG repeat and MBNL1 protein in the intranuclear foci of MD1 fetal tissues studied may theoretically result in sequestration of the protein and thus contribute to generation of the MD1 phenotype.

• Klíčová slova
• proteiny MBNL, fetální tkáň, DMPK mutace,
• MeSH
• fenotyp MeSH
• fluorescenční mikroskopie MeSH
• genetická transkripce genetika   MeSH
• histologické techniky MeSH
• hybridizace in situ fluorescenční MeSH
• imunohistochemie MeSH
• lidé MeSH
• molekulární sekvence - údaje MeSH
• mutační analýza DNA MeSH
• myotonická dystrofie * diagnóza   genetika   MeSH
• nemoci plodu MeSH
• otcové MeSH
• pitva MeSH
• plod * cytologie   patologie   MeSH
• polymerázová řetězová reakce MeSH
• protein-serin-threoninkinasy genetika   MeSH
• proteiny vázající RNA genetika   MeSH
• repetitivní sekvence nukleových kyselin MeSH
• ribonukleoproteiny genetika   MeSH
• rodokmen MeSH
• Southernův blotting MeSH
• zdraví rodiny MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• práce podpořená grantem MeSH
• techniky in vitro MeSH

The mRNA-protein complexes (mRNPs, Messenger ribonucleoprotein particles) are the "couriers" of the modern eukaryotes that process, store and deliver messages (transcripts) from the nucleus to the appropriate subcellular compartments and beyond. Presence of mRNPs arbitrates the posttranscriptional control of gene expression by editing the precursor RNA to maturity, postulate its subcellular localization and/or storage and dictate its fate once in the cytoplasm; either to be translated or dispensed through mRNA degradation. Initiation of transcription is coupled with processing of the transcribed message and the immediate association of the transcript with a set of structural and regulatory proteins. Per se, mRNP complexes sub-optimize transcription by recruiting RNA-binding proteins which are the core component of the RNP activities that culminate overall distribution and abundance of individual proteins. This asymmetric distribution of the mRNA is the determinant of protein gradient and is known to influence cell polarity, cell fate and overall patterning during development. Embryo patterning in Drosophila, polarization of maternal mRNA to daughter cell in budding yeast and directional growth of mammalian neural cell and pollen tubes of flowering plants, are the most prominent examples of mRNP facilitated posttranscriptional control, influencing cell fates and patterns of development.This chapter addresses the current knowledge on the mechanisms of posttranscriptional control reinforced by the formation of RNP particles and reviews differences in the underlying mechanisms. The outline of the chapter encompasses step-wise cellular processes leading to the formation of mRNPs and its implication to cellular activities. A dedicated section is also integrated discussing the recent findings on the unique mechanism of RNP formation in the male gametophyte of Nicotiana tabaccum. A proposed model outlines the network of posttranscriptional control with a focus on the role of RNPs is also presented aiming to stimulate future research with a perspective of advancing our knowledge on the subject and its plausible application in improving food quality.

• MeSH
• biologické modely MeSH
• cytoskelet metabolismus   MeSH
• lidé MeSH
• messenger RNA genetika   metabolismus   MeSH
• posttranskripční úpravy RNA MeSH
• proteiny vázající RNA genetika   metabolismus   MeSH
• ribonukleoproteiny genetika   metabolismus   MeSH
• stabilita RNA MeSH
• transport proteinů MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• přehledy MeSH