Název: Functional analysis of cryoprotectant system in Chymomyza costata
Autoři: GRGAC, Robert
Typ dokumentu: Disertační práce
Rok: 2023
Jazyk: eng
Abstrakt: In this study, employing an integrated approach that involves transcriptomics, metabolomics, and other techniques, we aimed to understand the mechanistic roles of the cryoprotective system underlying extreme freeze tolerance in the larvae of the drosophilid fly, Chymomyza costata. Metabolomics unveiled the complex composition of the seasonally accumulated larval innate mixture of putative cryoprotectants. This mixture was predominantly composed of proline and trehalose, supplemented by minor components (glutamine, asparagine, betaine, sarcosine, glycerophospho-choline, and ethanolamine). We identified food ingestion as a significant source for the direct assimilation of amino compounds, while glycogen and phospholipids served as the primary internal sources for the biosynthesis of other cryoprotectants. The utilization of MALDI-MSI to observe cryoprotectants revealed distinct behaviors of proline and trehalose during ecologically relevant, gradual inoculative extracellular freezing of larvae. Trehalose exhibited accumulation in partially dehydrated hemolymph, inducing a transition to the amorphous glass phase. On the other hand, proline migrated to the boundary between extracellular ice and dehydrated hemolymph and tissues, forming a layer of dense viscoelastic liquid. Finally, through a combination of in vivo and in vitro assays, we found that cell membranes are likely targets of freezing injury, while their integrity is sustained by accumulated small cryoprotective molecules and proteins in cold-acclimated C. costata larvae. Contrary to our expectations, our assays did not provide support for the hypothesis that proteins (soluble enzymes) require in vivo stabilization through the accumulation of cryoprotectants.
Citace: GRGAC, Robert. Functional analysis of cryoprotectant system in Chymomyza costata. České Budějovice, 2023. disertační práce (Ph.D.). JIHOČESKÁ UNIVERZITA V ČESKÝCH BUDĚJOVICÍCH. Přírodovědecká fakulta

Instituce: Jihočeská univerzita v Českých Budějovicích (web)
Informace o dostupnosti dokumentu: Plný text je dostupný v digitálním repozitáři JČU.
Původní záznam: http://www.jcu.cz/vskp/59225

Trvalý odkaz NUŠL: http://www.nusl.cz/ntk/nusl-540605


Záznam je zařazen do těchto sbírek:
Školství > Veřejné vysoké školy > Jihočeská univerzita v Českých Budějovicích
Vysokoškolské kvalifikační práce > Disertační práce