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Studium živých organismů bylo vždy zájmem vědeckých oborů a v dnešní době tomu není jinak. S moderními přístupy se otevírají nové možnosti, což souvisí i se značným rozmachem tzv. "omics" metod, kam patří například genomika, proteomika, metabolomika nebo glykomika. Lipidomika je nejmladším podoborem metabolomiky a zaměřuje se na analýzu lipidů v živých organismech. Lipidy jsou rozsáhlou skupinou přírodních látek, které jsou obsaženy v rostlinách, houbách, bakteriích nebo v těle živočichů, kde plní životně důležité funkce. Hmotnostní spektrometrie je nejpoužívanější technikou v kvalitativní i kvantitativní analýze lipidů. V teoretické části této práce jsou popsány základní poznatky o lipidech, současné názvosloví a biologické funkce v živých organismech. Současně je vysvětlena lipidomická analýza od přípravy vzorků až po nástroje využívané ke zpracování naměřených dat. Zvláštní pozornost je věnována principům chromatografických technik a využití jejich spojení s hmotnostní spektrometrií v lipidomické analýze, kdy jsou kromě výhod a limitací shrnuty také zásady pro kvalitativní a kvantitativní analýzu. Literární rešerše poté ukazuje potenciál lipidů pro diagnostiku různých typů onemocnění a přínos derivatizačních postupů v lipidomické analýze. V experimentální části je diskutován vývoj nových metod pro analýzu lipidů v tělních tekutinách s využitím spojení chromatografických technik a hmotnostní spektrometrie. V této práci jsou použity dva přístupy využívané v lipidomické analýze, separace lipidů dle lipidových druhů pomocí kapalinové chromatografie s obrácenými fázemi a separace dle lipidových tříd pomocí hydrofilní interakční chromatografie a superkritické fluidní chromatografie. Separace lipidů dle lipidových druhů je aplikována pro kvalitativní popis lidské plazmy s využitím klasického i derivatizačního přístupu, naopak metody založené na separaci dle lipidových tříd jsou využity pro kvantitativní analýzu velkého množství vzorků a pomocí statistických nástrojů jso, The living organisms have always been studied by scientific disciplines, and it is also valid at the present time. New modern approaches open new possibilities, which relates to the considerable expansion of "omics" methods including genomics, proteomics, metabolomics, or glycomics. Lipidomics is the youngest subgroup of metabolomics focusing on the analysis of lipids in living organisms. Lipids are a large group of natural substances, which are contained in plants, fungi, bacteria, or in the body of animals, where they are responsible for essential life functions. Mass spectrometry is the most widely used technique in the qualitative and quantitative analysis of lipids. The theoretical part of this thesis describes the basic knowledge about lipids, systematic nomenclature, and biological functions in living organisms. At the same time, the lipidomic analysis is described from sample preparation to data processing. A special attention is paid to the principles of chromatographic techniques associated with mass spectrometry for lipidomic analysis, and advantages, disadvantages, and principles of qualitative and quantitative analysis are summarized. The review shows the potential of lipids for the diagnosis of various types of diseases and the benefits of derivatization procedures in lipidomic analysis. The experimental part deals with the development of new methods for the analysis of lipids in body fluids by chromatographic techniques coupled with mass spectrometry. Lipidomic analysis follows two chromatographic approaches in this thesis, lipid species separation is achieved by reversed-phase liquid chromatography and lipid class separation by hydrophilic interaction chromatography and supercritical fluid chromatography. Lipid species separation is used for the qualitative analysis of human plasma by nonderivatization and derivatization approaches. On the other hand, the lipid class separation is used for the quantitative analysis of a large number of samples, and s, Fakulta chemicko-technologická, Dokončená práce s úspěšnou obhajobou

Studium živých organismů bylo vždy zájmem vědeckých oborů a v dnešní době tomu není jinak. S moderními přístupy se otevírají nové možnosti, což souvisí i se značným rozmachem tzv. "omics" metod, kam patří například genomika, proteomika, metabolomika nebo glykomika. Lipidomika je nejmladším podoborem metabolomiky a zaměřuje se na analýzu lipidů v živých organismech. Lipidy jsou rozsáhlou skupinou přírodních látek, které jsou obsaženy v rostlinách, houbách, bakteriích nebo v těle živočichů, kde plní životně důležité funkce. Hmotnostní spektrometrie je nejpoužívanější technikou v kvalitativní i kvantitativní analýze lipidů. V teoretické části této práce jsou popsány základní poznatky o lipidech, současné názvosloví a biologické funkce v živých organismech. Současně je vysvětlena lipidomická analýza od přípravy vzorků až po nástroje využívané ke zpracování naměřených dat. Zvláštní pozornost je věnována principům chromatografických technik a využití jejich spojení s hmotnostní spektrometrií v lipidomické analýze, kdy jsou kromě výhod a limitací shrnuty také zásady pro kvalitativní a kvantitativní analýzu. Literární rešerše poté ukazuje potenciál lipidů pro diagnostiku různých typů onemocnění a přínos derivatizačních postupů v lipidomické analýze. V experimentální části je diskutován vývoj nových metod pro analýzu lipidů v tělních tekutinách s využitím spojení chromatografických technik a hmotnostní spektrometrie. V této práci jsou použity dva přístupy využívané v lipidomické analýze, separace lipidů dle lipidových druhů pomocí kapalinové chromatografie s obrácenými fázemi a separace dle lipidových tříd pomocí hydrofilní interakční chromatografie a superkritické fluidní chromatografie. Separace lipidů dle lipidových druhů je aplikována pro kvalitativní popis lidské plazmy s využitím klasického i derivatizačního přístupu, naopak metody založené na separaci dle lipidových tříd jsou využity pro kvantitativní analýzu velkého množství vzorků a pomocí statistických nástrojů jso, The living organisms have always been studied by scientific disciplines, and it is also valid at the present time. New modern approaches open new possibilities, which relates to the considerable expansion of "omics" methods including genomics, proteomics, metabolomics, or glycomics. Lipidomics is the youngest subgroup of metabolomics focusing on the analysis of lipids in living organisms. Lipids are a large group of natural substances, which are contained in plants, fungi, bacteria, or in the body of animals, where they are responsible for essential life functions. Mass spectrometry is the most widely used technique in the qualitative and quantitative analysis of lipids. The theoretical part of this thesis describes the basic knowledge about lipids, systematic nomenclature, and biological functions in living organisms. At the same time, the lipidomic analysis is described from sample preparation to data processing. A special attention is paid to the principles of chromatographic techniques associated with mass spectrometry for lipidomic analysis, and advantages, disadvantages, and principles of qualitative and quantitative analysis are summarized. The review shows the potential of lipids for the diagnosis of various types of diseases and the benefits of derivatization procedures in lipidomic analysis. The experimental part deals with the development of new methods for the analysis of lipids in body fluids by chromatographic techniques coupled with mass spectrometry. Lipidomic analysis follows two chromatographic approaches in this thesis, lipid species separation is achieved by reversed-phase liquid chromatography and lipid class separation by hydrophilic interaction chromatography and supercritical fluid chromatography. Lipid species separation is used for the qualitative analysis of human plasma by nonderivatization and derivatization approaches. On the other hand, the lipid class separation is used for the quantitative analysis of a large number of samples, and s, Fakulta chemicko-technologická, Dokončená práce s úspěšnou obhajobou

This paper describes a novel type of nuclear structure - nuclear lipid islets (NLIs). They are of 40-100 nm with a lipidic interior, and phosphatidylinositol 4,5-bisphosphate [PtdIns(4,5)P-2] molecules comprise a significant part of their surface. Most of NLIs have RNA at the periphery. Consistent with that, RNA is required for their integrity. The NLI periphery is associated with Pol II transcription machinery, including the largest Pol II subunit, transcription factors and NM1 (also known as NMI). The Ptdlns(4,5)P-2-NM1 interaction is important for Pol II transcription, since NM1 knockdown reduces the Pol II transcription level, and the overexpression of wild-type NM1 [but not NM1 mutated in the Ptdlns(4,5)P-2-binding site] rescues the transcription. Importantly, Pol II transcription is dependent on NLI integrity, because an enzymatic reduction of the Ptdlns(4,5)P-2 level results in a decrease of the Pol II transcription level. Furthermore, about half of nascent transcripts localise to NLIs, and transcriptionally active transgene loci preferentially colocalise with NLIs. We hypothesize that NLIs serve as a structural platform that facilitates the formation of Pol II transcription factories, thus participating in the formation of nuclear architecture competent for transcription., V článku jsou popsány nové typy nukleárních struktur - nukleárních lipidových ostrůvků (NLIs). Skládají se z 40-100 nm lipidického interiéru a podstatnou část jejich povrchu tvoří molekuly fosfatidylinositol 4,5-bifofátu. Většina NLIs má na okraji RNA, která zajišťuje jejich integritu. Okraj NLI je spojován s Pol II transkripční mašinérií zahrnující největší Pol II podjednotku, trankripční faktory a NM1 (známou také jako NMI). PdIns(4,5)P-2-NM1 interakce je důležitá pro Poll II transkripci, protože NM1 knockdown snižuje úroveň Pol II transkripce, což přispívá k přebytku divokého druhu NM1. Co je však důležité, že Poll II transkripce je závislá na integritě NLI , protože enzymatická redukce Ptdlns(4,5)P-2 má za následek snížení úrovně Poll transkripce.

Species boundaries are traditionally inferred using morphological characters, although morphology sometimes fails to correctly delineate species. To overcome this limitation, researchers have widely taken advantage of alternative methods such as DNA barcoding or analysis of cuticular hydrocarbons (CHs) profiles, but rarely use them simultaneously in an iterative taxonomic approach. Here, we follow such an approach using morphology, DNA barcoding and CHs profiles to precisely discriminate species of soldierless termites, a diversified clade constituting about one-third of the Neotropical termite species richness, but poorly resolved taxonomically due to the paucity of useful characters. We sampled soldierless termites in various forest types of the Nouragues Nature Reserve, French Guiana. Our results show that morphological species determination generally matches DNA barcoding, which only suggests the existence of three cryptic species in the 31 morphological species. Among them, Longustitermes manni is the only species whose splitting is corroborated by ecological data, other widely distributed species being supported by DNA barcoding. On the contrary, although CHs profiles provide a certain taxonomic signal, they often suggest inconsistent groupings which are not supported by other methods. Overall, our data support DNA barcoding and morphology as two efficient methods to distinguish soldierless termite species. © 2013 Elsevier Inc., SCOPUS: ar.j, info:eu-repo/semantics/published

Species boundaries are traditionally inferred using morphological characters, although morphology sometimes fails to correctly delineate species. To overcome this limitation, researchers have widely taken advantage of alternative methods such as DNA barcoding or analysis of cuticular hydrocarbons (CHs) profiles, but rarely use them simultaneously in an iterative taxonomic approach. Here, we follow such an approach using morphology, DNA barcoding and CHs profiles to precisely discriminate species of soldierless termites, a diversified clade constituting about one-third of the Neotropical termite species richness, but poorly resolved taxonomically due to the paucity of useful characters. We sampled soldierless termites in various forest types of the Nouragues Nature Reserve, French Guiana. Our results show that morphological species determination generally matches DNA barcoding, which only suggests the existence of three cryptic species in the 31 morphological species. Among them, Longustitermes manni is the only species whose splitting is corroborated by ecological data, other widely distributed species being supported by DNA barcoding. On the contrary, although CHs profiles provide a certain taxonomic signal, they often suggest inconsistent groupings which are not supported by other methods. Overall, our data support DNA barcoding and morphology as two efficient methods to distinguish soldierless termite species. © 2013 Elsevier Inc., SCOPUS: ar.j, info:eu-repo/semantics/published

Labial glands are present in all castes and developmental stages of all termite species. In workers, their secretion contains a food-marking pheromone and digestive enzymes, while soldier secretion plays a defensive role. However, these functions were studied only in a limited set of species, and do not allow drawing general conclusions. Hence, we have investigated the chemical composition of the labial gland extracts from soldiers and workers in 15 termite species belonging to 6 families using an integrative approach based on proteomic and small-molecule profiling. We confirmed the presence of hydroquinone and cellulase in the labial glands of workers, and we identified new toxic compounds in soldiers and workers of several species. Our results highlight the dual role of labial gland secretion, i.e. the defensive role in soldiers and workers of several termite species, and the digestive function in workers., Journal Article, Research Support, Non-U.S. Gov't, SCOPUS: ar.j, info:eu-repo/semantics/published

Labial glands are present in all castes and developmental stages of all termite species. In workers, their secretion contains a food-marking pheromone and digestive enzymes, while soldier secretion plays a defensive role. However, these functions were studied only in a limited set of species, and do not allow drawing general conclusions. Hence, we have investigated the chemical composition of the labial gland extracts from soldiers and workers in 15 termite species belonging to 6 families using an integrative approach based on proteomic and small-molecule profiling. We confirmed the presence of hydroquinone and cellulase in the labial glands of workers, and we identified new toxic compounds in soldiers and workers of several species. Our results highlight the dual role of labial gland secretion, i.e. the defensive role in soldiers and workers of several termite species, and the digestive function in workers.

Labial glands are present in all castes and developmental stages of all termite species. In workers, their secretion contains a food-marking pheromone and digestive enzymes, while soldier secretion plays a defensive role. However, these functions were studied only in a limited set of species, and do not allow drawing general conclusions. Hence, we have investigated the chemical composition of the labial gland extracts from soldiers and workers in 15 termite species belonging to 6 families using an integrative approach based on proteomic and small-molecule profiling. We confirmed the presence of hydroquinone and cellulase in the labial glands of workers, and we identified new toxic compounds in soldiers and workers of several species. Our results highlight the dual role of labial gland secretion, i.e. the defensive role in soldiers and workers of several termite species, and the digestive function in workers.

Labial glands are present in all castes and developmental stages of all termite species. In workers, their secretion contains a food-marking pheromone and digestive enzymes, while soldier secretion plays a defensive role. However, these functions were studied only in a limited set of species, and do not allow drawing general conclusions. Hence, we have investigated the chemical composition of the labial gland extracts from soldiers and workers in 15 termite species belonging to 6 families using an integrative approach based on proteomic and small-molecule profiling. We confirmed the presence of hydroquinone and cellulase in the labial glands of workers, and we identified new toxic compounds in soldiers and workers of several species. Our results highlight the dual role of labial gland secretion, i.e. the defensive role in soldiers and workers of several termite species, and the digestive function in workers.

Labial glands are present in all castes and developmental stages of all termite species. In workers, their secretion contains a food-marking pheromone and digestive enzymes, while soldier secretion plays a defensive role. However, these functions were studied only in a limited set of species, and do not allow drawing general conclusions. Hence, we have investigated the chemical composition of the labial gland extracts from soldiers and workers in 15 termite species belonging to 6 families using an integrative approach based on proteomic and small-molecule profiling. We confirmed the presence of hydroquinone and cellulase in the labial glands of workers, and we identified new toxic compounds in soldiers and workers of several species. Our results highlight the dual role of labial gland secretion, i.e. the defensive role in soldiers and workers of several termite species, and the digestive function in workers., Journal Article, Research Support, Non-U.S. Gov't, SCOPUS: ar.j, info:eu-repo/semantics/published