Juvenile hormones (JHs) are lipophilic signals of vital importance to insects and related arthropods, representing the most successful group of animals on our planet. Among species relying on regulation by JH are beneficial pollinators and crustaceans, as well as agricultural pests and disease vectors. Manipulation of JH signaling is a good target for insecticide control. Therefore, knowledge of JH signaling is important both for fundamental science and for practical use. The intracellular JH receptor has been identified, largely through work in the host laboratory, but its action is still poorly understood. Current evidence suggests that activity of this JH receptor is modulated by JH-induced phosphorylation. The objective of this proposal is to identify the phosphorylation target sites and to determine their significance for the JH receptor function. To achieve this goal, the status of amino acid residues potentially phosphorylated in response to JH will be determined using mass spectrometry of the JH receptor protein expressed in insect cell lines. The key residues will be mutated either to prevent phosphorylation or to mimic a constitutively phosphorylated state, and the mutant receptors will be examined for capacity to bind JH, induce JH-response genes, and sustain normal insect development in vivo. The approach thus ranges from protein biochemistry through cell-based assays to developmental genetics employing the Drosophila model. The goals are achievable through the combined expertise of the Applicant, extensively trained in protein chemistry and molecular biology at the top-ranking US universities, and the host laboratory of Dr. Marek Jindra, who is among the leaders in insect developmental endocrinology and JH research in particular. This project will enable the Applicant to fully expand her potential and learn insect developmental genetics while permanently integrating to European science.

Mitochondria perform three essential functions: ATP production, metabolite synthesis and cellular signaling. These signals, communicating the bioenergetic and biosynthetic fitness of the organelle to the nucleus, play a powerful role in determining cellular fate. The incorporation of mitochondrial reactive oxygen species (mROS) in cellular signaling is an interesting evolutionary outcome, as excess levels of these potent oxidizers have been implicated in many pathologies. While most research focuses on these outcomes of oxidative stress, much less is known about how mROS drive a range of physiological responses. Furthermore, the available studies are limited to a few traditional model organisms, featuring complex cellular systems with numerous mitochondria at different energetic states. Here, we propose to utilize the unicellular parasites, Trypanosoma brucei and T. congolense, as simplified but elegant models to define mROS-driven cellular differentiation. As these protists undergo programmed development between several distinct life cycle forms, there are striking changes to the structure and physiology of their single mitochondrion that manifest in elevated ROS levels. Importantly, we demonstrated that these ROS molecules are essential for the developmental progression of the parasite. Employing these well-chosen models and combining next-generation biosensors, advanced bioenergetic methods, redox proteomics and a CRISPR/Cas9 genetic screen, we will answer the following fundamental questions: Does mROS drive Trypanosoma cellular differentiation? What molecular processes are responsible for the elevated mROS levels during differentiation? How is the redox signal propagated to the rest of the cell? The proposed research aspires to unravel the fundamental mechanisms underlying the intricate communication between mitochondria and the rest of the cell, featuring cellular hallmarks of cell fate decisions.

One of the most challenging tasks in ecology is to reclaim landscapes being disturbed by anthropogenic activities. Many human endeavours have been put forth for improving microbial activities and their structures, soil organic carbon level and plant reestablishment after depleting the top earth. Global use of pyrogenic carbon shows promising prospect on C sequestration and soil restoration, but there is a noticeable delayed advancement in improving its benefits. In accordance to UN Climate Smart Agriculture and UN Sustainable Development Goals, this project will seek a novel strategy for soil restoration by using pyrogenic carbon and core microbial communities (CBMs), to gain multiple benefits including aspects of waste management, C sequestration and plant regeneration. The project will make use of unique habitats for CBMs selection at both a long-term natural successional post mining site and a well-recorded reclaimed meadow in Czech Republic, Central Europe. The main objective of this project is to assess if pyrogenic carbon could ensure the function of CBMs during their transplantations from donor to recipient soils: 1) disentangle the ‘refuge’ effect of pyrogenic carbon on CBMs from macro-fauna by isotopic analysis, and microbial oxidation effect on pore structures and hydrophobicity of pyrogenic carbon, and 2) clarify the compositions of CBMs and their functions to responsive plant species in undeveloped soils. The transfer of knowledge between the host institution and the candidate will pave a solid way for the researcher’s scientific career, and future collaborations between the researcher, the host and the secondment are foreseen. Altogether, this project will provide a promising potential to increase the competitiveness of EU in using bio-wastes and soil inoculants for circular economy by bridging in waste management and soil restoration.

Polycomb Repressive Complex 2 (PRC2) is an evolutionarily conserved histone methyltransferase complex that catalyses trimethylation of lysine 27 of histone H3 (H3K27me3), which leads to epigenetic gene repression. In Arabidopsis thaliana (A. thaliana), CURLY LEAF (CLF) and SWINGER (SWN) are two major H3K27 methyltransferases and core components of PRC2 in the sporophyte, playing essential roles in the regulation of plant development. However, the knowledge of how PRC2 participates in operational control in plants is scarce. Recently, altered phenotypes of PRC2-depletion mutants grown under different light intensities were observed. Hence, here I raise the hypothesis that PRC2 acts in fully differentiated cells to modulate the ambient light acclimation. At first, short- and long-term light acclimation responses that require PRC2 activity will be identified, employing plant morphology and physiology tools. Next, PRC2-governed molecular mechanisms and PRC2-modulated light signaling pathway in the light acclimation will be established. Molecular tools (RNA-seq and ChIP-seq) will be used to profile transcriptome and H3K27me3 distribution to establish the patterns of epigenome and transcriptome alteration in WT and mutants. At last, the focus will expand to select other chromatin modification mutants displaying altered light acclimation responses. In summary, for the first time, dynamics of PRC2 repression in fully differentiated cells in response to light acclimation will be determined and it will lay a solid foundation for studying other chromatin modifiers in future. The project builds on combining my experience in plant physiology and ecology and gaining research experience in the field of developmental epigenetics. The fellowship proposal is designed in a way to enhance my independent thinking capacity, organizational and management skills and responsibilities, which are necessary to become an excellent and independent researcher and group leader in the future.