Description of research area
- Phylogenetic relationships within Hemiptera at a suborder rank: Sternorrhyncha, Fulgoromorpha et Cicadomorpha and Heteroptera
In this scientific project we analyze morphological, histochemical and molecular characteristics to determine what evolutionary tendencies they indicate. On the basis of the results, we define evolutionary changes among selected groups of Hemiptera of different taxonomic ranks (families, tribes and genera). Relationships are verified with the usage of data on morphology and ultrastructure of the reproductive system and the morphology of the selected body tagmata. Molecular markers (mitochondrial and nucleic ones) are also used. When palaeontological criteria and intra- and extra-group comparisons are incorporated, the structural changes in skeletal elements are recognized as indicative of morphological change tendencies.
- Developmental strategies of animals (Insecta, Aranea, Oligochaeta, Gastropoda) under environmental stress.
Research focus on comparative analysis of embryonic development and life-history of different species with the special attention paid on metabolic and growth rate and dynamics of subsequent developmental stages appearance. Physiological and biochemical measures of females’ reproductive strategies under quantitative and qualitative stressors’ variations are investigated. Developmental potential of the embryos and possible mechanisms of their (pre-) adaptations and/or tolerance of different stressors is determined. Laboratory-derived strains of insects (Spodoptera exigua, Acheta domesticus) obtained during multigenerational selection toward different longevity or metal tolerance are unique biological material also used in toxicological studies.
- Organization of reproductive systems and gametogenesis in selected invertebrates (Clitellata, Tardigrada, Insecta)
This field of research is concentrated on description of reproductive systems and the course of spermatogenesis and oogenesis in selected invertebrates as clitellate annelids, tardigrades and some insects (aphids). The special attention is paid on the architecture, formation and functioning of germ-cell clusters (cysts). Within the clusters the organization and role of cytoskeleton and organelle (e.g. mitochondria) transfer is additionally analyzed. The morphological, histological and ultrastructural characters of reproductive system organization are used for better understanding of phylogenetic relationships in the studied taxa.
- The development, structure and functions of the midgut epithelium of invertebrates (e.g., Hexapoda, Crustacea, Myriapoda, Tardigrada)
The project is connected with the ultrastructural analysis of the midgut epithelium in invertebrates, with the special emphasis on the midgut degeneration (e.g., apoptosis, necrosis, autophagy) and its regeneration. Histo- and immunohistochemical methods are used in order to analyze mechanisms of the cell death and regenerative processes (e.g., regenerative cells proliferation and differentiation), and the establishing the role of the midgut epithelium according to stressors that originate from the external environment (e.g., pathogens, metals, xenobiotics, starvation, etc.). Additionally, the development of the digestive system (mainly the midgut) during both, the embryogenesis and larval development is examined using mentioned above methods. 3D imaging is useful in preparing reconstructions of the digestive system in adults and all developmental stages. - Organs differentiation during embryonic development of vertebrate animals
Studies are connected with embryonic development of squamate reptiles (Squamata). The project concerns following issues:
- Comparative studies of the thyroid development in lizards and snakes
- Pancreas morphogenesis in snake embryos
- Embryonic development of the vomeronasal organ (Jacobson’s organ) and associated structures in different squamate reptiles
- Gametogenesis during embryonic development in different squamate reptiles
- Differentiation of the egg tooth in different squamate reptiles
- Differentiation of the tongue in different squamate reptiles
- Embryonic development of the lateral and the parietal eyes in different squamate reptiles
- Differentiation of circadian clock centers in squamate reptiles
- Comparison of keratinization processes within covering of the body and surface of the tongue in squamate reptiles
- Differentiation of the muscles in different Squamata species
Anatomical, morphological, histological and immunocytochemical features of differentiating Squamata organs are used in phylogenetical analyses.
Methods:
- light microscopy (light and dark field, phase contrast) and fluorescence microscopy
- electron microscopy: transmission (TEM) and scanning (SEM) with the usage of low vacuum chamber (Phenom) and high vacuum chamber (Hitachi, Phenom);
- histo- and immunohistochemistry
- In vito cell culturing, live cell imaging
- 3D imaging of cells and tissues (SBFEM, X-ray, µCT)
- image cytometry
- X-ray computed microtomography
- Genotoxicity and DNA oxidative damage tests
- Luminescence assays for measurements of energy potential of cells
- Atomic absorption spectrometry (AAS)
- ELISA, Western Blotting (HSPs; metallothioneins);
- Electrophoresis assays (isoenzymes’ profiles);
- UV-VIS spectrometry and spectrofluorometry (enzyme activity, low-molecular-weight antioxidants content, detection of free radicals);
- respirometric measurements of metabolic rate in small animals;
- measurements of calorific values of organic matter and energy budget in insects;
- degree of kinship revision by molecular markers: mitochondrial cytochrome I oxidase gene, and other ones;
- comparative analysis of morphological and histochemical traits in modern forms and fossils at species and trans specific levels;
- identification of evolutionary changes in morphology by morphometric, anatomical and molecular traits comparison