The function of the plant hormone jasmonic acid (JA) in the development of tomato (Solanum lycopersicum) flowers was analyzed with a mutant defective in JA perception (jasmonate-insensitive1-1, jai1-1). In contrast with Arabidopsis (Arabidopsis thaliana) JA-insensitive plants, which are male sterile, the tomato jai1-1 mutant is female sterile, with major defects in female development. To identify putative JA-dependent regulatory components, we performed transcriptomics on ovules from flowers at three developmental stages from wild type and jai1-1 mutants. One of the strongly downregulated genes in jai1-1 encodes the MYB transcription factor SlMYB21. Its Arabidopsis ortholog plays a crucial role in JA-regulated stamen development. SlMYB21 was shown here to exhibit transcription factor activity in yeast, to interact with SlJAZ9 in yeast and in planta, and to complement Arabidopsis myb21-5 To analyze SlMYB21 function, we generated clustered regularly interspaced short palindromic repeats(CRISPR)/CRISPR associated protein 9 (Cas9) mutants and identified a mutant by Targeting Induced Local Lesions in Genomes (TILLING). These mutants showed female sterility, corroborating a function of MYB21 in tomato ovule development. Transcriptomics analysis of wild type, jai1-1, and myb21-2 carpels revealed processes that might be controlled by SlMYB21. The data suggest positive regulation of JA biosynthesis by SlMYB21, but negative regulation of auxin and gibberellins. The results demonstrate that SlMYB21 mediates at least partially the action of JA and might control the flower-to-fruit transition.
.

• MeSH
• cyklopentany metabolismus   MeSH
• down regulace MeSH
• fenotyp MeSH
• fertilita MeSH
• gibereliny metabolismus   MeSH
• květy genetika   fyziologie   MeSH
• kyseliny indoloctové metabolismus   MeSH
• mutace MeSH
• neplodnost rostlin MeSH
• ovoce genetika   fyziologie   MeSH
• oxylipiny metabolismus   MeSH
• proteiny huseníčku genetika   metabolismus   MeSH
• regulace genové exprese u rostlin * MeSH
• regulátory růstu rostlin metabolismus   MeSH
• rostlinné proteiny genetika   metabolismus   MeSH
• Solanum lycopersicum genetika   fyziologie   MeSH
• transkripční faktory genetika   metabolismus   MeSH
• vajíčko rostlin genetika   fyziologie   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Leaf senescence is an essential physiological process in plants that supports the recycling of nitrogen and other nutrients to support the growth of developing organs, including young leaves, seeds, and fruits. Thus, the regulation of senescence is crucial for evolutionary success in wild populations and for increasing yield in crops. Here, we describe the influence of a NAC transcription factor, SlNAP2 (Solanum lycopersicum NAC-like, activated by Apetala3/Pistillata), that controls both leaf senescence and fruit yield in tomato (S. lycopersicum). SlNAP2 expression increases during age-dependent and dark-induced leaf senescence. We demonstrate that SlNAP2 activates SlSAG113 (S. lycopersicum SENESCENCE-ASSOCIATED GENE113), a homolog of Arabidopsis (Arabidopsis thaliana) SAG113, chlorophyll degradation genes such as SlSGR1 (S. lycopersicum senescence-inducible chloroplast stay-green protein 1) and SlPAO (S. lycopersicum pheide a oxygenase), and other downstream targets by directly binding to their promoters, thereby promoting leaf senescence. Furthermore, SlNAP2 directly controls the expression of genes important for abscisic acid (ABA) biosynthesis, S. lycopersicum 9-cis-epoxycarotenoid dioxygenase 1 (SlNCED1); transport, S. lycopersicum ABC transporter G family member 40 (SlABCG40); and degradation, S. lycopersicum ABA 8'-hydroxylase (SlCYP707A2), indicating that SlNAP2 has a complex role in establishing ABA homeostasis during leaf senescence. Inhibiting SlNAP2 expression in transgenic tomato plants impedes leaf senescence but enhances fruit yield and sugar content likely due to prolonged leaf photosynthesis in aging tomato plants. Our data indicate that SlNAP2 has a central role in controlling leaf senescence and fruit yield in tomato.

• MeSH
• dioxygenasy genetika   metabolismus   MeSH
• geneticky modifikované rostliny MeSH
• genový knockdown MeSH
• kyselina abscisová genetika   metabolismus   MeSH
• listy rostlin fyziologie   MeSH
• ovoce genetika   růst a vývoj   MeSH
• regulace genové exprese u rostlin MeSH
• rostlinné proteiny genetika   metabolismus   MeSH
• Solanum lycopersicum genetika   růst a vývoj   MeSH
• systém (enzymů) cytochromů P-450 genetika   metabolismus   MeSH
• tma MeSH
• transkripční faktory genetika   metabolismus   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Sex determination in Rumex acetosa, a dioecious plant with a complex XY1 Y2 sex chromosome system (females are XX and males are XY1 Y2 ), is not controlled by an active Y chromosome but depends on the ratio between the number of X chromosomes and autosomes. To gain insight into the molecular mechanisms of sex determination, we generated a subtracted cDNA library enriched in genes specifically or predominantly expressed in female floral buds in early stages of development, when sex determination mechanisms come into play. In the present paper, we report the molecular and functional characterization of FEM32, a gene encoding a protein that shares a common architecture with proteins in different plants, animals, bacteria and fungi of the aerolysin superfamily; many of these function as β pore-forming toxins. The expression analysis, assessed by northern blot, RT-PCR and in situ hybridization, demonstrates that this gene is specifically expressed in flowers in both early and late stages of development, although its transcripts accumulate much more in female flowers than in male flowers. The ectopic expression of FEM32 under both the constitutive promoter 35S and the flower-specific promoter AP3 in transgenic tobacco showed no obvious alteration in vegetative development but was able to alter floral organ growth and pollen fertility. The 35S::FEM32 and AP3::FEM32 transgenic lines showed a reduction in stamen development and pollen viability, as well as a diminution in fruit set, fruit development and seed production. Compared with other floral organs, pistil development was, however, enhanced in plants overexpressing FEM32. According to these effects, it is likely that FEM32 functions in Rumex by arresting stamen and pollen development during female flower development. The aerolysin-like pore-forming proteins of eukaryotes are mainly involved in defence mechanisms against bacteria, fungi and insects and are also involved in apoptosis and programmed cell death (PCD), a mechanism that could explain the role of FEM32 in Rumex sex determination.

• MeSH
• bakteriální toxiny klasifikace   genetika   MeSH
• cytotoxické proteiny tvořící póry klasifikace   genetika   MeSH
• fylogeneze MeSH
• geneticky modifikované rostliny MeSH
• květy genetika   růst a vývoj   MeSH
• neplodnost rostlin genetika   MeSH
• ovoce genetika   růst a vývoj   MeSH
• pyl genetika   růst a vývoj   MeSH
• regulace genové exprese u rostlin MeSH
• rostlinné proteiny klasifikace   genetika   MeSH
• Rumex genetika   růst a vývoj   MeSH
• sekvence aminokyselin MeSH
• sekvenční homologie aminokyselin MeSH
• semena rostlinná genetika   růst a vývoj   MeSH
• stanovení celkové genové exprese metody   MeSH
• tabák genetika   růst a vývoj   MeSH
• vývojová regulace genové exprese MeSH
• Publikační typ
• časopisecké články MeSH

Camu-camu [Myrciaria dubia (Kunth) McVaugh] is currently an important and promising fruit species grown in the Peruvian Amazon, as well as in Brazil, Colombia, and Bolivia. The species is valued for its high content of fruit-based vitamin C. Large plantations have been established only in the last two decades, and a substantial part of the production is still obtained by collecting fruits from the wild. Domestication of the species is at an early stage; most farmers cultivate the plants without any breeding, or only through a simple mass selection process. The main objective of the study was to characterize morphological and genetic variation within and among cultivated and natural populations of camu-camu in the Peruvian Amazon. In total, we sampled 13 populations: ten wild in the Iquitos region, and three cultivated in the Pucallpa region in the Peruvian Amazon. To assess the genetic diversity using seven microsatellite loci, we analyzed samples from ten individual trees per each population (n = 126). Morphological data was collected from five trees from each population (n = 65). The analysis did not reveal statistically significant differences for most of the morphological descriptors. For wild and cultivated populations, the observed heterozygosity was 0.347 and 0.404 (expected 0.516 and 0.506), and the fixation index was 0.328 and 0.200, respectively. Wild populations could be divided into two groups according to the UPGMA and STRUCTURE analysis. In cultivated populations, their approximate origin was determined. Our findings indicate a high genetic diversity among the populations, but also a high degree of inbreeding within the populations. This can be explained by either the isolation of these populations from each other or the low number of individuals in some populations. This high level of genetic diversity can be explored for the selection of superior individuals for further breeding.

• MeSH
• DNA rostlinná genetika   MeSH
• genetická variace genetika   MeSH
• mikrosatelitní repetice genetika   MeSH
• Myrtaceae anatomie a histologie   genetika   MeSH
• ovoce anatomie a histologie   genetika   MeSH
• stromy anatomie a histologie   genetika   MeSH
• Publikační typ
• časopisecké články MeSH
• Geografické názvy
• Peru MeSH

The hop metabolome important for the brewing industry and for medical purposes is endangered worldwide due to multiple viroid infections affecting hop physiology. Combinatorial biolistic hop inoculation with Citrus bark cracking viroid (CBCVd), Apple fruit crinkle viroid (AFCVd), Hop latent viroid, and Hop stunt viroid (HSVd) showed a low CBCVd compatibility with HSVd, while all other viroid combinations were highly compatible. Unlike to other viroids, single CBCVd propagation showed a significant excess of (-) over (+) strands in hop, tomato, and Nicotiana benthamiana, but not in citruses. Inoculation of hop with all viroids led to multiple infections with unstable viroid levels in individual plants in the pre- and post-dormancy periods, and to high plant mortality and morphological disorders. Hop isolates of CBCVd and AFCVd were highly stable, only minor quasispecies were detected. CBCVd caused a strong suppression of some crucial mRNAs related to the hop prenylflavonoid biosynthesis pathway, while AFCVd-caused effects were moderate. According to mRNA degradome analysis, this suppression was not caused by a direct viroid-specific small RNA-mediated degradation. CBCVd infection led to a strong induction of two hop transcription factors from WRKY family and to a disbalance of WRKY/WDR1 complexes important for activation of lupulin genes.

• MeSH
• Citrus genetika   virologie   MeSH
• Humulus genetika   virologie   MeSH
• kvantitativní polymerázová řetězová reakce MeSH
• Malus genetika   virologie   MeSH
• messenger RNA genetika   MeSH
• ovoce genetika   virologie   MeSH
• tabák genetika   virologie   MeSH
• viroidy genetika   patogenita   MeSH
• Publikační typ
• časopisecké články MeSH

Understanding how plants cope with changing habitats is a timely and important topic in plant research. Phenotypic plasticity describes the capability of a genotype to produce different phenotypes when exposed to different environmental conditions. In contrast, the constant production of a set of distinct phenotypes by one genotype mediates bet hedging, a strategy that reduces the temporal variance in fitness at the expense of a lowered arithmetic mean fitness. Both phenomena are thought to represent important adaptation strategies to unstable environments. However, little is known about the underlying mechanisms of these phenomena, partly due to the lack of suitable model systems. We used phylogenetic and comparative analyses of fruit and seed anatomy, biomechanics, physiology, and environmental responses to study fruit and seed heteromorphism, a typical morphological basis of a bet-hedging strategy of plants, in the annual Brassicaceae species Aethionema arabicum Our results indicate that heteromorphism evolved twice within the Aethionemeae, including once for the monophyletic annual Aethionema clade. The dimorphism of Ae. arabicum is associated with several anatomic, biomechanical, gene expression, and physiological differences between the fruit and seed morphs. However, fruit ratios and numbers change in response to different environmental conditions. Therefore, the life-history strategy of Ae. arabicum appears to be a blend of bet hedging and plasticity. Together with the available genomic resources, our results pave the way to use this species in future studies intended to unravel the molecular control of heteromorphism and plasticity.

• MeSH
• biologické modely MeSH
• Brassicaceae anatomie a histologie   embryologie   genetika   ultrastruktura   MeSH
• down regulace genetika   MeSH
• fenotyp MeSH
• fylogeneze MeSH
• klíčení genetika   MeSH
• ovoce embryologie   genetika   ultrastruktura   MeSH
• regulace genové exprese u rostlin MeSH
• rostlinné geny MeSH
• rostlinné proteiny genetika   metabolismus   MeSH
• sekvenční homologie aminokyselin MeSH
• semena rostlinná embryologie   genetika   ultrastruktura   MeSH
• šíření semen MeSH
• vývojová regulace genové exprese MeSH
• vývojové geny MeSH
• Publikační typ
• časopisecké články MeSH

Salinization of water and soil has a negative impact on tomato (Solanum lycopersicum L.) productivity by reducing growth of sink organs and by inducing senescence in source leaves. It has been hypothesized that yield stability implies the maintenance or increase of sink activity in the reproductive structures, thus contributing to the transport of assimilates from the source leaves through changes in sucrolytic enzymes and their regulation by phytohormones. In this study, classical and functional physiological approaches have been integrated to study the influence of metabolic and hormonal factors on tomato fruit sink activity, growth, and yield: (i) exogenous hormones were applied to plants, and (ii) transgenic plants overexpressing the cell wall invertase (cwInv) gene CIN1 in the fruits and de novo cytokinin (CK) biosynthesis gene IPT in the roots were constructed. Although salinity reduces fruit growth, sink activity, and trans-zeatin (tZ) concentrations, it increases the ethylene precursor 1-aminocyclopropane-1-carboxylic acid (ACC) during the actively growing period (25 days after anthesis). Indeed, exogenous application of the CK analogue kinetin to salinized actively growing fruits recovered sucrolytic activities (mainly cwInv and sucrose synthase), sink strength, and fruit weight, whereas the ethylene-releasing compound ethephon had a negative effect in equivalent non-stressed fruits. Fruit yield was increased by both the constitutive expression of CIN1 in the fruits (up to 4-fold) or IPT in the root (up to 30%), owing to an increase in the fruit number (lower flower abortion) and in fruit weight. This is possibly related to a recovery of sink activity in reproductive tissues due to both (i) increase in sucrolytic activities (cwInv, sucrose synthase, and vacuolar and cytoplasmic invertases) and tZ concentration, and (ii) a decrease in the ACC levels and the activity of the invertase inhibitor. This study provides new functional evidences about the role of metabolic and hormonal inter-regulation of local sink processes in controlling tomato fruit sink activity, growth, and yield under salinity.

• MeSH
• biomasa MeSH
• buněčná stěna enzymologie   MeSH
• chlorid sodný farmakologie   MeSH
• cytokininy metabolismus   MeSH
• exprese genu MeSH
• geneticky modifikované rostliny MeSH
• invertasa genetika   metabolismus   MeSH
• kořeny rostlin účinky léků   genetika   metabolismus   MeSH
• květy účinky léků   genetika   metabolismus   MeSH
• kyselina abscisová metabolismus   MeSH
• ovoce účinky léků   genetika   metabolismus   MeSH
• regulátory růstu rostlin farmakologie   MeSH
• rostlinné proteiny genetika   metabolismus   MeSH
• sacharosa metabolismus   MeSH
• salinita MeSH
• sekvestrace uhlíku MeSH
• Solanum lycopersicum účinky léků   genetika   metabolismus   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Nežádoucí účinky léčiv, jejich toxicita a často samotná účinnost léčiv závisí významně na jejich metabolizmu, který je určujícím faktorem aktivace a/nebo eliminace příslušné látky. U lidí jsou nejvýznamnějšími enzymy metabolizujícími léčiva v první fázi jejich biotransformace cytochromy P450. Aktivita těchto enzymů se může lišit v důsledku interindividuální genetické variability, ale také může být ovlivněna indukcí nebo inhibicí enzymů jejich substráty nebo jinými látkami, a to nejen léčivy. Vedle účinků vlastního léčiva či interakcí s léčivy současně podávanými jsou opomíjeny látky, které se vyskytují v životním prostředí, nejvýznamněji v potravě, a mohou metabolizmus léčiv také ovlivnit. Některé běžně užívané rostlinné drogy, ovoce, ale stejně tak například alkohol nebo kouření mohou způsobit selhání farmakoterapie až závažné poškození zdraví pacienta. Tento článek přináší stručný přehled potenciálně nebezpečných nutričních faktorů včetně přípravků z rostlinných drog (mj. čaje, nálevy), které by měly být brány v úvahu při zavádění individuální farmakoterapie. Nejdůležitějšími rizikovými faktory ve výživě a životním stylu interagujícími s metabolizmem léčiv jsou v první řadě grapefruit, pomelo, karambola, granátová jablka a některé další exotické ovoce, třezalka tečkovaná (Hypericum perforatum), kofein, a rovněž alkohol a kouření cigaret.

Drug side effects and toxicity and often the drug efficacy are highly dependent on drug metabolism determining the activation and/or elimination of the respective compound. In humans, cytochromes P450 are the most important drug metabolizing enzymes of the first phase of drug biotransformation. Their activity can vary due to interindividual genetic differences, but it can be changed also by inhibition or induction of the enzymes by their substrates or other compounds that are not only drugs themselves and/or drugs taken concomitantly. Often, influence on drug metabolism by compounds that occur in the environment, most remarkably in the food, is forgotten. Some commonly used herbs, fruits as well as e.g. alcohol may cause failure of the therapy up to serious alterations of the patient’s health. This review presents a brief overview of potentially dangerous nutrition factors including herbs (incl. teas, infusions) that should be considered when indicating individual drug therapy. Examples include primarily grapefruits, pomelo, star fruit, pomegranates and some other fruits, St John’s Wort (Hypericum perforatum), caffeine, as well as alcohol and cigarette smoking.

• MeSH
• biotransformace genetika   imunologie   účinky léků   MeSH
• finanční podpora výzkumu jako téma MeSH
• kofein MeSH
• lékové interakce fyziologie   genetika   imunologie   MeSH
• lidé MeSH
• ovoce genetika   imunologie   škodlivé účinky   MeSH
• pití alkoholu imunologie   metabolismus   škodlivé účinky   MeSH
• potraviny škodlivé účinky   MeSH
• potravní doplňky škodlivé účinky   toxicita   MeSH
• systém (enzymů) cytochromů P-450 metabolismus   škodlivé účinky   MeSH
• třezalka genetika   imunologie   škodlivé účinky   MeSH
• Check Tag
• lidé MeSH