In root research, hydroponic plant cultivation is commonly used and soil experiments are rare. We investigated the response of 12-day-old barley roots, cultivated in soil-filled rhizotrons, to different soil water potentials (SWP) comparing a modern cultivar (cv. Scarlett) with a wild accession ICB181243 from Pakistan. Water potentials were quantified in soils with different relative water contents. Root anatomy was studied using histochemistry and microscopy. Suberin and lignin amounts were quantified by analytical chemistry. Transcriptomic changes were observed by RNA-sequencing. Compared with control with decreasing SWP, total root length decreased, the onset of endodermal suberization occurred much closer towards the root tips, amounts of suberin and lignin increased, and corresponding biosynthesis genes were upregulated in response to decreasing SWP. We conclude that decreasing water potentials enhanced root suberization and lignification, like osmotic stress experiments in hydroponic cultivation. However, in soil endodermal cell suberization was initiated very close towards the root tip, and root length as well as suberin amounts were about twofold higher compared with hydroponic cultivation.

• Klíčová slova
• apoplastic root barrier, lignin, soil water potential, soil water stress, soil‐grown barley root, suberin,
• MeSH
• dehydratace MeSH
• hydroponie * MeSH
• ječmen (rod) * genetika   růst a vývoj   metabolismus   fyziologie   MeSH
• kořeny rostlin * metabolismus   růst a vývoj   MeSH
• lignin metabolismus   MeSH
• lipidy analýza   biosyntéza   MeSH
• půda * chemie   MeSH
• regulace genové exprese u rostlin MeSH
• voda * metabolismus   MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• lignin MeSH
• lipidy MeSH
• půda * MeSH
• suberin MeSH Prohlížeč
• voda * MeSH

The molecular mechanisms linking obstructive sleep apnea syndrome (OSA) to obesity and the development of metabolic diseases are still poorly understood. The role of hypoxia (a characteristic feature of OSA) in excessive fat accumulation has been proposed. The present study investigated the possible effects of hypoxia (4% oxygen) on de novo lipogenesis by tracking the major carbon sources in differentiating 3T3-L1 adipocytes. Gas-permeable cultuware was employed to cultivate 3T3-L1 adipocytes in hypoxia (4%) for 7 or 14 days of differentiation. We investigated the contribution of glutamine, glucose or acetate using 13C or 14C labelled carbons to the newly synthesized lipid pool, changes in intracellular lipid content after inhibiting citrate- or acetate-dependent pathways and gene expression of involved key enzymes. The results demonstrate that, in differentiating adipocytes, hypoxia decreased the synthesis of lipids from glucose (44.1 ± 8.8 to 27.5 ± 3.0 pmol/mg of protein, p < 0.01) and partially decreased the contribution of glutamine metabolized through the reverse tricarboxylic acid cycle (4.6% ± 0.2-4.2% ± 0.1%, p < 0.01). Conversely, the contribution of acetate, a citrate- and mitochondria-independent source of carbons, increased upon hypoxia (356.5 ± 71.4 to 649.8 ± 117.5 pmol/mg of protein, p < 0.01). Further, inhibiting the citrate- or acetate-dependent pathways decreased the intracellular lipid content by 58% and 73%, respectively (p < 0.01) showing the importance of de novo lipogenesis in hypoxia-exposed adipocytes. Altogether, hypoxia modified the utilization of carbon sources, leading to alterations in de novo lipogenesis in differentiating adipocytes and increased intracellular lipid content.

• MeSH
• acetáty * metabolismus   farmakologie   MeSH
• buněčná diferenciace * účinky léků   MeSH
• buňky 3T3-L1 * MeSH
• citrátový cyklus MeSH
• glukosa * metabolismus   MeSH
• glutamin * metabolismus   MeSH
• hypoxie buňky MeSH
• lipidy biosyntéza   MeSH
• lipogeneze * účinky léků   MeSH
• metabolismus lipidů účinky léků   MeSH
• myši MeSH
• tukové buňky * metabolismus   účinky léků   MeSH
• zvířata MeSH
• Check Tag
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• acetáty * MeSH
• glukosa * MeSH
• glutamin * MeSH
• lipidy MeSH

Increasing evidence suggests that posttranscriptional regulation is a key player in the transition between mature pollen and the progamic phase (from pollination to fertilization). Nonetheless, the actors in this messenger RNA (mRNA)-based gene expression reprogramming are poorly understood. We demonstrate that the evolutionarily conserved RNA-binding protein LARP6C is necessary for the transition from dry pollen to pollen tubes and the guided growth of pollen tubes towards the ovule in Arabidopsis thaliana. In dry pollen, LARP6C binds to transcripts encoding proteins that function in lipid synthesis and homeostasis, vesicular trafficking, and polarized cell growth. LARP6C also forms cytoplasmic granules that contain the poly(A) binding protein and possibly represent storage sites for translationally silent mRNAs. In pollen tubes, the loss of LARP6C negatively affects the quantities and distribution of storage lipids, as well as vesicular trafficking. In Nicotiana benthamiana leaf cells and in planta, analysis of reporter mRNAs designed from the LARP6C target MGD2 provided evidence that LARP6C can shift from a repressor to an activator of translation when the pollen grain enters the progamic phase. We propose that LARP6C orchestrates the timely posttranscriptional regulation of a subset of mRNAs in pollen during the transition from the quiescent to active state and along the progamic phase to promote male fertilization in plants.

• MeSH
• 5' nepřekládaná oblast MeSH
• Arabidopsis cytologie   genetika   růst a vývoj   MeSH
• cytoplazmatická granula genetika   metabolismus   MeSH
• geneticky modifikované rostliny MeSH
• lipidy biosyntéza   genetika   MeSH
• messenger RNA genetika   metabolismus   MeSH
• proteiny huseníčku genetika   metabolismus   MeSH
• proteiny vázající RNA genetika   metabolismus   MeSH
• pylová láčka cytologie   genetika   růst a vývoj   MeSH
• regulace genové exprese u rostlin MeSH
• RNA rostlin metabolismus   MeSH
• tabák genetika   MeSH
• vazba proteinů MeSH
• vazebná místa MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• 5' nepřekládaná oblast MeSH
• AT3G19090 protein, Arabidopsis MeSH Prohlížeč
• lipidy MeSH
• messenger RNA MeSH
• proteiny huseníčku MeSH
• proteiny vázající RNA MeSH
• RNA rostlin MeSH

The aim of the study was to identify the optimum cultivation conditions for the microalgal growth and lipid production of the oleaginous microalga Chlorella pyrenoidosa Chick (IPPAS C2). Moreover, an appropriate NO3- concentration in the cultivation medium for maximized lipid accumulation was determined. The experimental design involved a biphasic cultivation strategy with an initial biomass accumulating phase under optimized light (400 μmol/m2 per s), temperature (25 °C), and elevated CO2 concentration in the air mixture (3%), followed by a mid-elevated CO2 concentration (0.5%) for lipid induction. The highest lipid yields of 172.47 ± 18.1 and 179.65 ± 25.4 mg/L per day were detected for NO3- concentrations of 100 and 150 mg/L. The optimization approach presented here led not only to the maximization of lipid yield but also to the development of a biphasic cultivation strategy easily applicable to the cultivation process without the necessity for algal cell harvesting between the first and second cultivation phases.

• MeSH
• biomasa MeSH
• Chlorella růst a vývoj   metabolismus   MeSH
• dusičnany metabolismus   MeSH
• fotobioreaktory MeSH
• kultivační média metabolismus   MeSH
• lipidy biosyntéza   MeSH
• mikrořasy růst a vývoj   metabolismus   MeSH
• oxid uhličitý metabolismus   MeSH
• techniky vsádkové kultivace MeSH
• teplota MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• dusičnany MeSH
• kultivační média MeSH
• lipidy MeSH
• oxid uhličitý MeSH

Dual stable isotope probing has been used to infer rates of microbial biomass production and modes of carbon fixation. In order to validate this approach for assessing archaeal production, the methanogenic archaeon Methanosarcina barkeri was grown either with H2 , acetate or methanol with D2 O and 13 C-dissolved inorganic carbon (DIC). Our results revealed unexpectedly low D incorporation into lipids, with the net fraction of water-derived hydrogen amounting to 0.357 ± 0.042, 0.226 ± 0.003 and 0.393 ± 0.029 for growth on H2 /CO2 , acetate and methanol respectively. The variability in net water H assimilation into lipids during the growth of M. barkeri on different substrates is possibly attributed to different Gibbs free energy yields, such that higher energy yield promoted the exchange of hydrogen between medium water and lipids. Because NADPH likely serves as the portal for H transfer, increased NADPH production and/or turnover associated with high energy yield may explain the apparent differences in net water H assimilation into lipids. The variable DIC and water H incorporation into M. barkeri lipids imply systematic, metabolic patterns of isotope incorporation and suggest that the ratio of 13 C-DIC versus D2 O assimilation in environmental samples may serve as a proxy for microbial energetics in addition to microbial production and carbon assimilation pathways.

• MeSH
• acetáty metabolismus   MeSH
• lipidy biosyntéza   MeSH
• methanol metabolismus   MeSH
• Methanosarcina barkeri růst a vývoj   metabolismus   MeSH
• oxid uhličitý metabolismus   MeSH
• uhlík metabolismus   MeSH
• vodík metabolismus   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• acetáty MeSH
• lipidy MeSH
• methanol MeSH
• oxid uhličitý MeSH
• uhlík MeSH
• vodík MeSH

Pericellular oxygen concentration represents an important factor in the regulation of cell functions, including cell differentiation, growth and mitochondrial energy metabolism. Hypoxia in adipose tissue has been associated with altered adipokine secretion profile and suggested as a possible factor in the development of type 2 diabetes. In vitro experiments provide an indispensable tool in metabolic research, however, physical laws of gas diffusion make prolonged exposure of adherent cells to desired pericellular O2 concentrations questionable. The aim of this study was to investigate the direct effect of various O2 levels (1%, 4% and 20% O2) on the proteomic profile and triglyceride accumulation in 3T3-L1 differentiated preadipocytes using gas-permeable cultureware. Following differentiation of cells under desired pericellular O2 concentrations, cell lysates were subjected to two-dimensional gel electrophoresis and protein visualization using Coomassie blue staining. Spots showing differential expression under hypoxia were analyzed using matrix-assisted laser desorption/ionization mass spectrometry. All identified proteins were subjected to pathway analysis. We observed that protein expression of 26 spots was reproducibly affected by 4% and 1% O2 (17 upregulated and 9 downregulated). Pathway analysis showed that mitochondrial energy metabolism and triglyceride synthesis were significantly upregulated by hypoxia. In conclusion, this study demonstrated the direct effects of pericellular O2 levels on adipocyte energy metabolism and triglyceride synthesis, probably mediated through the reversed tricarboxylic acid cycle flux.

• MeSH
• 2D gelová elektroforéza MeSH
• buněčná diferenciace účinky léků   MeSH
• buňky 3T3-L1 MeSH
• citrátový cyklus účinky léků   MeSH
• down regulace účinky léků   MeSH
• kultivované buňky MeSH
• kyslík farmakologie   MeSH
• lipidy biosyntéza   MeSH
• lipogeneze účinky léků   MeSH
• myši MeSH
• permeabilita MeSH
• plyny chemie   MeSH
• počet buněk MeSH
• proteomika * MeSH
• spektrometrie hmotnostní - ionizace laserem za účasti matrice MeSH
• triglyceridy metabolismus   MeSH
• tukové buňky cytologie   účinky léků   metabolismus   MeSH
• upregulace účinky léků   MeSH
• zvířata MeSH
• Check Tag
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• kyslík MeSH
• lipidy MeSH
• plyny MeSH
• triglyceridy MeSH

BACKGROUND: Adipocytes are cells specialized for storage of neutral lipids. This storage capacity is dependent on lipogenesis and is diminished in obesity. The reason for the decline in lipogenic activity of adipocytes in obesity remains unknown. Recent data show that lipogenesis in liver is regulated by pathways initiated by endoplasmic reticulum stress (ERS). Thus, we aimed at investigating the effect of ERS on lipogenesis in adipose cells. METHODS: Preadipocytes were isolated from subcutaneous abdominal adipose tissue from obese volunteers and in vitro differentiated into adipocytes. ERS was induced pharmacologically by thapsigargin (TG) or tunicamycin (TM). Activation of Unfolded Protein Response pathway (UPR) was monitored on the level of eIF2α phosphorylation and mRNA expression of downstream targets of UPR sensors. Adipogenic and lipogenic capacity was evaluated by Oil Red O staining, measurement of incorporation of radio-labelled glucose or acetic acid into lipids and mRNA analysis of adipogenic/lipogenic markers. RESULTS: Exposition of adipocytes to high doses of TG (100 nM) and TM (1 μg/ml) for 1-24 h enhanced expression of several UPR markers (HSPA5, EDEM1, ATF4, XBP1s) and phosphorylation of eIF2α. This acute ERS substantially inhibited expression of lipogenic genes (DGAT2, FASN, SCD1) and glucose incorporation into lipids. Moreover, chronic exposure of preadipocytes to low dose of TG (2.5 nM) during the early phases of adipogenic conversion of preadipocytes impaired both, lipogenesis and adipogenesis. On the other hand, chronic low ERS had no apparent effect on lipogenesis in mature adipocytes. CONCLUSIONS: Acute ERS weakened a capacity of mature adipocytes to store lipids and chronic ERS diminished adipogenic potential of preadipocytes.

• Klíčová slova
• Adipocytes, Adipogenesis, Endoplasmic reticulum stress, Lipogenesis, Thapsigargin, Tunicamycin,
• MeSH
• buněčná diferenciace * MeSH
• chaperon endoplazmatického retikula BiP MeSH
• endoplazmatické retikulum účinky léků   metabolismus   MeSH
• fosforylace MeSH
• fyziologický stres * MeSH
• lidé MeSH
• lipidy biosyntéza   MeSH
• signální dráha UPR MeSH
• thapsigargin farmakologie   MeSH
• tukové buňky cytologie   MeSH
• tunikamycin farmakologie   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• chaperon endoplazmatického retikula BiP MeSH
• HSPA5 protein, human MeSH Prohlížeč
• lipidy MeSH
• thapsigargin MeSH
• tunikamycin MeSH

The alga Parachlorella kessleri, strain CCALA 255, grown under optimal conditions, is characterized by storage of energy in the form of starch rather than lipids. If grown in the complete medium, the cultures grew rapidly, producing large amounts of biomass in a relatively short time. The cells, however, contained negligible lipid reserves (1-10% of DW). Treatments inducing hyperproduction of storage lipids in P. kessleri biomass were described. The cultures were grown in the absence or fivefold decreased concentration of either nitrogen or phosphorus or sulfur. Limitation by all elements using fivefold or 10-fold diluted mineral medium was also tested. Limitation with any macroelement (nitrogen, sulfur, or phosphorus) led to an increase in the amount of lipids; nitrogen limitation was the most effective. Diluted nutrient media (5- or 10-fold) were identified as the best method to stimulate lipid overproduction (60% of DW). The strategy for lipid overproduction consists of the fast growth of P. kessleri culture grown in the complete medium to produce sufficient biomass (DW more than 10 g/L) followed by the dilution of nutrient medium to stop growth and cell division by limitation of all elements, leading to induction of lipid production and accumulation up to 60% DW. Cultivation conditions necessary for maximizing lipid content in P. kessleri biomass generated in a scale-up solar open thin-layer photobioreactor were described.

• MeSH
• biomasa MeSH
• biotechnologie MeSH
• chlorofyl analýza   metabolismus   MeSH
• Chlorophyta metabolismus   MeSH
• fotobioreaktory MeSH
• kultivační média MeSH
• lipidy biosyntéza   MeSH
• mastné kyseliny analýza   metabolismus   MeSH
• metabolismus lipidů MeSH
• mikrořasy metabolismus   MeSH
• oxid uhličitý metabolismus   MeSH
• škrob analýza   metabolismus   MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• chlorofyl MeSH
• kultivační média MeSH
• lipidy MeSH
• mastné kyseliny MeSH
• oxid uhličitý MeSH
• škrob MeSH

Novel rhamnolipid-producing strains of three thermophilic bacteria, Thermus sp., T. aquaticus and Meiothermus ruber were identified that have not been previously described as rhamnolipid producers. Rhamnolipids were extracted from supernatant and further purified by thin-layer chromatography. Mass spectrometry with negative electrospray ionization revealed 77 rhamnolipid homologues varying in chain length and unsaturation. Tandem mass spectrometry identified mono-rhamnolipid and di-rhamnolipid homologues containing one or two 3-hydroxy-fatty acids, saturated, monounsaturated or diunsaturated, even- or odd-chain, up to unusual long chains with 24 carbon atoms. The stereochemistry of rhamnose was L and that of 3-hydroxy-fatty acids was R, the position of double bonds in monoenoic acids was cis ω-9. All three strains produced a rhamnolipid that differs in structure from Pseudomonas aeruginosa rhamnolipids and exhibits excellent surfactant properties. Importantly, in comparison to P. aeruginosa both strains, i.e., Thermus and Meiothermus, are Biosafety level 1 microorganisms and are not pathogenic to humans.

• MeSH
• chromatografie na tenké vrstvě MeSH
• druhová specificita MeSH
• hmotnostní spektrometrie s elektrosprejovou ionizací MeSH
• lipidy analýza   biosyntéza   izolace a purifikace   MeSH
• stereoizomerie MeSH
• Thermus klasifikace   metabolismus   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• lipidy MeSH

OBJECT: Among several non-invasive methods of liver fat analysis, the most important role is played by MR imaging and spectroscopy (MRS). This study describes the 1H MRS at 3T measurement of liver fat volume fraction Φ(fat) in a group of liver transplant patients, an at-risk group for the development of de novo steatosis. MATERIALS AND METHODS: Seventy-seven liver transplant recipients who underwent routine protocolar posttransplant examination were divided into three groups: CON-PAT (control group for the cross validation test, 48 patients), PAT-PAT (patients test group for the cross validation test, 29 patients), and PAT (pooled data). Single voxel 1H MRS at 3T was used for the determination of Φ(fat) and histology results (His) were used as the reference standard. RESULTS: Linear and non-linear regression models were used to describe the relationship between Φ(fat) and His. Strong correlation was found for both models with r = 0.83-0.94 (P < 0.001); a higher r was found for non-linear regression in all tested groups. Areas under receiver operation curves were calculated for cut points His ≥ 5 and > 33% and were found in the range of 0.77-0.86. Fibrosis influences the calculation of Φ(fat) and different slopes were obtained for fibrosis stages F0-F1 and F2-F3, respectively. CONCLUSION: Significant correlation was found between the results of histology and 1H MRS measurement of liver fat content. The method is suitable for non-invasive repetitive examination of liver fat in liver-transplants patients between protocol biopsies and for the screening of steatosis in other liver diseases.

• MeSH
• biopsie MeSH
• deuterium MeSH
• dospělí MeSH
• játra chemie   patologie   patofyziologie   MeSH
• lidé středního věku MeSH
• lidé MeSH
• lineární modely MeSH
• lipidy biosyntéza   MeSH
• magnetická rezonanční spektroskopie metody   MeSH
• magnetická rezonanční tomografie metody   MeSH
• nelineární dynamika MeSH
• reprodukovatelnost výsledků MeSH
• senioři MeSH
• senzitivita a specificita MeSH
• transplantace jater metody   MeSH
• tuková tkáň chemie   MeSH
• ztučnělá játra diagnóza   metabolismus   patologie   MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• srovnávací studie MeSH
• Názvy látek
• deuterium MeSH
• lipidy MeSH