IN BRIEF: Understanding the establishment of post-fertilization totipotency has broad implications for modern biotechnologies. This review summarizes the current knowledge of putative egg components governing this process following natural fertilization and after somatic cell nuclear transfer. ABSTRACT: The mammalian oocyte is a unique cell, and comprehending its physiology and biology is essential for understanding fertilization, totipotency and early events of embryogenesis. Consequently, research in these areas influences the outcomes of various technologies, for example, the production and conservation of laboratory and large animals with rare and valuable genotypes, the rescue of the species near extinction, as well as success in human assisted reproduction. Nevertheless, even the most advanced and sophisticated reproductive technologies of today do not always guarantee a favorable outcome. Elucidating the interactions of oocyte components with its natural partner cell - the sperm or an 'unnatural' somatic nucleus, when the somatic cell nucleus transfer is used is essential for understanding how totipotency is established and thus defining the requirements for normal development. One of the crucial aspects is the stoichiometry of different reprogramming and remodeling factors present in the oocyte and their balance. Here, we discuss how these factors, in combination, may lead to the formation of a new organism. We focus on the laboratory mouse and its genetic models, as this species has been instrumental in shaping our understanding of early post-fertilization events.

• MeSH
• buněčné jádro * fyziologie   MeSH
• embryonální vývoj MeSH
• lidé MeSH
• myši MeSH
• oocyty fyziologie   MeSH
• savci MeSH
• sperma * MeSH
• spermie fyziologie   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• mužské pohlaví MeSH
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• přehledy MeSH

Green algae are fast-growing microorganisms that are considered promising for the production of starch and neutral lipids, and the chlorococcal green alga Parachlorella kessleri is a favorable model, as it can produce both starch and neutral lipids. P. kessleri commonly divides into more than two daughter cells by a specific mechanism-multiple fission. Here, we used synchronized cultures of the alga to study the effects of supra-optimal temperature. Synchronized cultures were grown at optimal (30 °C) and supra-optimal (40 °C) temperatures and incident light intensities of 110 and 500 μmol photons m-2 s-1. The time course of cell reproduction (DNA replication, cellular division), growth (total RNA, protein, cell dry matter, cell size), and synthesis of energy reserves (net starch, neutral lipid) was studied. At 40 °C, cell reproduction was arrested, but growth and accumulation of energy reserves continued; this led to the production of giant cells enriched in protein, starch, and neutral lipids. Furthermore, we examined whether the increased temperature could alleviate the effects of deuterated water on Parachlorella kessleri growth and division; results show that supra-optimal temperature can be used in algal biotechnology for the production of protein, (deuterated) starch, and neutral lipids.

• MeSH
• biomasa MeSH
• buněčné dělení fyziologie   MeSH
• Chlorophyta růst a vývoj   MeSH
• lipidy MeSH
• metabolismus lipidů fyziologie   MeSH
• mikrořasy metabolismus   MeSH
• škrob metabolismus   MeSH
• teplota * MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

BACKGROUND: Phlebotomine sand flies (Diptera, Nematocera) are important vectors of several pathogens, including Leishmania parasites, causing serious diseases of humans and dogs. Despite their importance as disease vectors, most aspects of sand fly biology remain unknown including the molecular basis of their reproduction and sex determination, aspects also relevant for the development of novel vector control strategies. RESULTS: Using comparative genomics/transcriptomics data mining and transcriptional profiling, we identified the sex determining genes in phlebotomine sand flies and proposed the first model for the sex determination cascade of these insects. For all the genes identified, we produced manually curated gene models, developmental gene expression profile and performed evolutionary molecular analysis. We identified and characterized, for the first time in a Nematocera species, the transformer (tra) homolog which exhibits both conserved and novel features. The analysis of the tra locus in sand flies and its expression pattern suggest that this gene is able to autoregulate its own splicing, as observed in the fruit fly Ceratitis capitata and several other insect species. CONCLUSIONS: Our results permit to fill the gap about sex determination in sand flies, contribute to a better understanding of this developmental pathway in Nematocera and open the way for the identification of sex determining orthologs in other species of this important Diptera sub-order. Furthermore, the sex determination genes identified in our work also provide the opportunity of future biotechnological applications to control natural population of sand flies, reducing their impact on public health.

• MeSH
• alternativní sestřih MeSH
• data mining MeSH
• fylogeneze MeSH
• genomika MeSH
• hmyzí proteiny chemie   genetika   MeSH
• messenger RNA genetika   MeSH
• molekulární evoluce * MeSH
• procesy určující pohlaví genetika   MeSH
• Psychodidae genetika   MeSH
• sekvence aminokyselin MeSH
• selekce (genetika) MeSH
• stanovení celkové genové exprese MeSH
• vývojová regulace genové exprese MeSH
• zvířata MeSH
• Check Tag
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

This review discusses the new biotechnological tools that are arising and promising for conservation and enhancement of fish production, mainly regarding the endangered and the most economically important species. Two main techniques, in particular, are available to avoid extinction of endangered fish species and to improve the production of commercial species. Germ cell transplantation technology includes a number of approaches that have been studied, such as the transplantation of embryo-to-embryo blastomere, embryo-to-embryo differentiated PGC, larvae to larvae and embryo differentiated PGC, transplantation of spermatogonia from adult to larvae or between adults, and oogonia transplantation. However, the success of germ cell transplantation relies on the prior sterilization of fish, which can be performed at different stages of fish species development by means of several protocols that have been tested in order to achieve the best approach to produce a sterile fish. Among them, fish hybridization and triploidization, germline gene knockdown, hyperthermia, and chemical treatment deserve attention based on important results achieved thus far. This review currently used technologies and knowledge about surrogate technology and fish sterilization, discussing the stronger and the weaker points of each approach.

• MeSH
• asistovaná reprodukce veterinární   MeSH
• biotechnologie MeSH
• rozmnožování MeSH
• ryby fyziologie   MeSH
• zachování přírodních zdrojů MeSH
• zárodečné buňky cytologie   transplantace   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH

The ongoing progress in primordial germ cell derivation and cultivation is opening new ways in reproductive biotechnology. This study tested whether functional sperm cells can be matured from genetically manipulated primordial germ cells after transplantation in adult testes and used to restore fertility. We show that spermatogenesis can be restored after mCherry-expressing or GFP-expressing primordial germ cells are transplantated into the testes of sterilized G0 roosters and that mCherry-positive or GFP-positive non-chimeric transgenic G1 offspring can be efficiently produced. Compared with the existing approaches to primordial germ cell replacement, this new technique eliminates the germ line chimerism of G0 roosters and is, therefore, faster, more efficient and requires fewer animals. Furthermore, this is the only animal model, where the fate of primordial germ cells in infertile recipients can be studied.

• MeSH
• fenotyp MeSH
• fertilita * MeSH
• kur domácí genetika   fyziologie   MeSH
• spermatogeneze genetika   MeSH
• spermie cytologie   MeSH
• technika přenosu genů * MeSH
• testis cytologie   fyziologie   MeSH
• transdukce genetická MeSH
• transplantace buněk * MeSH
• zvířata MeSH
• Check Tag
• mužské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Knowledge of embryo development is essential to the application of reproductive biotechnology in aquaculture, including for pikeperch Sander lucioperca. We describe pikeperch embryo development and demonstrated effects of temperature on the duration of embryogenesis. Developmental stages in embryos incubated at 15 °C were identified as zygote, 0-1.5 h post-fertilization (hpf); cleavage, 2.5-7.5 hpf; blastula, 9-18.75 hpf; gastrula, 21-39, hpf; segmentation, 45-105 hpf; and hatching, 125-197 hpf. Additional groups of eggs were fertilized and incubated at 10, 15, 20, and 25 °C to document stages of development, development rate, and survival. The optimal fertilization and incubation temperature was shown to be 15 °C, with the highest fertilization, survival, and hatching rates. Embryo development was slower at 10 °C, with 45% of fertilized embryos surviving to hatching. Development was accelerated at 20 °C, and resulted in a 56% survival rate of fertilized embryos. At 25 °C, embryos did not develop to the blastula stage. Pikeperch could be a valuable percid model for research in which flexible incubation temperatures is required.

• MeSH
• embryo nesavčí fyziologie   MeSH
• embryonální vývoj MeSH
• Perciformes embryologie   MeSH
• teplota * MeSH
• voda * MeSH
• zvířata MeSH
• Check Tag
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

Starch and lipids are key components of algal cells and responsible for buffering variable supplies of energy and carbon that are vital for cell growth and reproduction, particularly DNA replication, nuclear and cellular division. The basic characteristics of energy reserves, their ultrastructure and localization inside the cell, regulation of their synthesis in relation to cell cycle phases, and their control by external factors, including light intensity, temperature, and carbon dioxide are described. Over the last two decades, research in this field has been boosted by possible biotechnological applications of algae for the production of biofuels from energy conserving compounds (bioethanol from starch and biodiesel from lipids). Recent findings on mechanisms that lead to an accumulation of exceptionally high levels of starch and lipids in algae will be summarized in this review. Macroelement (N, S, P) limitation, or depletion in mineral medium, as the most widely used approaches for enhancing both starch and lipid accumulation, are reviewed in detail. Potential biotechnological strategies for the economically viable overproduction of lipid and starch, such as a two-step procedure exploiting the effects of nutrient limitation and depletion, as well as the means and rationale for selecting appropriate strains, are discussed.

• MeSH
• biotechnologie metody   MeSH
• buněčný cyklus * MeSH
• druhová specificita MeSH
• energetický metabolismus * MeSH
• Eukaryota metabolismus   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• přehledy MeSH

Ergot alkaloids are widely used in the pharmaceutical industry in drug preparations for treating migraines and Parkinson's disease, inducing uterine contraction, and other purposes. Phytopathogenic fungi of the genus Claviceps (e.g. C. purpurea) comprise a major biological source of ergot alkaloids. Worldwide industrial production of these alkaloids derives almost equally from two biotechnological procedures: submerged culture of the fungus in fermenters and field parasitic production in dormant fungal organs known as sclerotia (also termed ergot). Ergot yields from field cultivation are greatly affected by weather and also can be much reduced by pollen contamination from imperfectly male-sterile rye, as only unfertilized ovaries can be infected by C. purpurea spores. Two substances with gametocidal effect - maleic hydrazide and 2-chloroethylphosphonic acid - were tested during three consecutive seasons in small field experiments for the ability to induce or amplify the male sterility of rye as well as the impacts on germination of C. purpurea spores and general vitality of rye host plants. Maleic hydrazide was proven to be a highly effective gametocide on both a fertile rye variety and a variety with imperfectly induced cytoplasmic male sterility. It showed negligible effect on germination of C. purpurea spores. Both accurate dosaging of the active gametocidal compound and timing of the application just 2-3 weeks before onset of anthesis proved crucial to achieving high ergot yield with minimum grain impurities.

• MeSH
• hydrazid kyseliny maleinové aplikace a dávkování   MeSH
• námelové alkaloidy biosyntéza   izolace a purifikace   MeSH
• neplodnost rostlin účinky léků   fyziologie   MeSH
• organofosforové sloučeniny aplikace a dávkování   MeSH
• regulátory růstu rostlin farmakologie   MeSH
• upregulace účinky léků   fyziologie   MeSH
• vztah mezi dávkou a účinkem léčiva MeSH
• zárodečné buňky rostlin účinky léků   MeSH
• žito účinky léků   metabolismus   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

V současné době se v České republice novorozeneckým screeningem vyhledává 10 různých dědičných metabolických poruch a na základě výsledků probíhající pilotní studie je plánováno spektrum vyhledávaných chorob rozšířit. Rozšiřování panelu novorozeneckého screeningu vždy otevírá základní etickou otázku týkající se výběru onemocnění, která mají být do panelu zařazena. Jako vodítko stále slouží tradiční kritéria výběru screenovaných onemocnění, přestože nové biotechnologie a vědecké poznatky zkomplikovaly náhled na jejich univerzální aplikovatelnost. Stejně jako každý jiný screeningový program, přináší novorozenecký screening pro sledovanou populaci nejenom prospěch plynoucí z včasného stanovení diagnózy a zahájení léčby, ale i rizika, mezi která patří detekce klinicky nezávažných stavů, falešně negativní a falešně pozitivní výsledky. Pro nově zařazená onemocnění je proto nutné odborně posoudit, zda je správně vyvážen poměr prospěchu a rizik. Důležitým hodnotícím kritériem je i hledisko efektivity vynaložených finančních zdrojů a jejich vyváženost vzhledem k ostatním oblastem zdravotnictví. Úkolem novorozeneckého screeningového programu je pro všechna nová i dříve zařazená onemocnění pravidelně vyhodnocovat úspěšnost a efektivitu jeho provádění, hledat biotechnologická řešení vedoucí k minimalizaci rizik spojených s jeho prováděním a zajistit odpovídající informovanost rodičů.

Newborn screening program in the Czech Republic includes 10 inherited metabolic disorders and its expansion is planned as a result of ongoing pilot study. Which disorders should be added and what criteria used for their selection are the key ethical questions closely connected with every screening panel expansion. Traditional screening criteria can function as guidelines even if their universal applicability has been questioned by new biotechnologies and scientific progress. Apart from the benefit from early diagnosis and effective treatment the newborn screening program also poses risks from false-positive and false-negative results as well as detection of conditions with no clinical significance. Before adding a new disorder to the screening panel it is necessary to evaluate the balance between health benefits and potential harms. Furthermore it is important to assess its cost-effectiveness also from the perspective of the whole healthcare system. All newborn screening programs need to evaluate these aspects regularly also for already established panel of diseases and search for new biotechnological solutions to minimize associated risks. Another essential task is to provide parents with all the necessary information in accessible form.

• MeSH
• falešně negativní reakce MeSH
• falešně pozitivní reakce MeSH
• lidé MeSH
• novorozenec MeSH
• novorozenecký screening MeSH
• plošný screening etika   MeSH
• reprodukční chování MeSH
• riziko MeSH
• vrozené poruchy metabolismu * diagnóza   ekonomika   MeSH
• Check Tag
• lidé MeSH
• novorozenec MeSH
• Publikační typ
• práce podpořená grantem MeSH