Scientific team projects

Structure and regulation of small mammal parasite communities and their intestinal microflora

Projects leader: Asta Križanauskienė

Terms of the project: 2017–2020

In the course of coevolution, a host, its parasites and microbiota have developed as a complex system where each component plays a significant role by interacting with each other and seeking to maintain homeostasis. Such multicomponential system is constantly affected by a variety of factors which determine the structure and changes of parasite communities and their microbiota. The assessment of such factors and the elucidation of regulation mechanisms are necessary in order to understand the functioning of the system in natural populations as well as to identify  and control epizooses and dangerous-to-humans zoonoses.

The aim of the project is to identify the factors decisive for the structure of parasite communities and intestinal microbiota and its regulation mechanisms in natural small mammal populations.

The tasks of the project are 1) to investigate the species composition of small mammal parasite communities and intestinal microbiota as well as to estimate the intensity of infestation with parasites and assess their genetic diversity; 2) to identify the factors decisive for the structure of parasite communities and intestinal microbiota as well as regulation mechanisms: environmental (habitat, feeding conditions and diet, seasonality), populational (species composition, abundance, age and gender structure, genealogy of host communities), genetic-evolutionary (phylogeny, genetic structure of populations); 3) to perform a comparative analysis of the effect of factors and regulation mechanisms on parasite communities and intestinal microbiota; 4) to determine causative agents of zoonoses potentially hazardous to humans and domestic animals, as well as to identify their major reservoir hosts and host communities where a probability for successful establishment and distribution of diseases is the highest.

Holocene multi-proxy environmental reconstructions and climate dynamics: spatial and temporal context

Projects leader: dr. Miglė Stančikaitė

Terms of the project: 2017–2020

Holocene palaeoenvironmental and palaeoclimatic investigations provide an insight into the climatic and environmental history thus giving an opportunity to put contemporary changes into the long chronological perspective. Although an increasing number of derived proxies has provided independent information sources for the further interpretations and generalisations around the North Atlantic realm, the eastward situated territory of the continent has largely remained as “unknown” from the point of view of Holocene palaeo-history as the majority of the old data is insufficient from today’s perspective.

To address this challenge we suggest the high-resolution multi-proxy analysis of lake/peat sequences in order to get high temporal-spatial resolution of Holocene environmental and climatic changes along the Kaliningrad-N Poland-Lithuania-Belarus gradient covering transitional climatic (oceanic-continental) and floristic (boreo-nemoral) zones. Similar territories are more sensitive to climatic and environmental shifts. The project focuses on the combination of high-resolution multi-proxy studies of pollen, diatom, chironomid, plant macrofossil records alongside with geochemical, loss-on-ignition, grain-size, mineral magnetic and 14C measurements of sediment sequences.

The project aims at reconstruction of Holocene environmental change and climatic dynamics along the W-E gradient in the oceanic-continental and boreo-nemoral ecotonal transitional zones through a high temporal resolution multi-proxy study of natural sedimentary archives.

The tasks of the project are a) to explore the development of Holocene vegetation along the W-E transect discussing pattern of local and regional changes; b) based on the identified abiotic and biotic markers to characterize the sedimentary response of lacustrine systems during the periods of climatic shifts of different magnitude; c) for the first time in the region to discuss the temporal and spatial magnitude of Holocene climate variability based on chironomid data; d) based on the newly defined chronological framework of the identified environmental and climatic shifts to correlate this data with regional and global records; and e) to assess the interface between the recorded changes and those identified along the North Atlantic realm.

We suppose that it is essential to improve our knowledge of environmental history and climatic dynamics which could aid in gaining understanding of both regional and global evolution.

Assessment of toxicity of different stressor types to aquatic organisms

Projects leader: dr. Laura Butrimavičienė

Terms of the project: 2017–2020

The project focuses on assessment of toxicity of different stressor types (chemical and physical) to different aquatic organisms in different stages of development. The aim of the project is to assess under laboratory conditions the toxicological significance of biological effects caused by chemical and physical stressors of different composition and origin in aquatic organisms as well as their recovery after removal of stressors. The following phenomena will be considered during implementation of the project: a) chemical stressors detected in real concentrations in the environment cause toxicologically significant effects; b) the effect of a physical stressor of anthropogenic origin on organisms in the environment and subsequent biological effects; and c) recovery of organisms after removal of stressors.

Experimental investigations will involve several species of freshwater and marine organisms (fishes, molluscs) in different stages of their development. The toxicity of stressors will be given systematic assessment, i.e. the effects caused will be assessed from subcell to organism level. A wide spectrum of biomarkers will be applied, namely cytogenetic, biochemical, cytological and physiological biomarkers. As an indicator of environmental stress, an integrated response of biomarkers will be calculated. Such response is important and helpful in assessing ecological risks and can be applied in environmental protection management.


Investigations into diversity of genus Sarcocystis parasites from Cervidae and cattle

Projects leader: dr. Petras Prakas

Terms of the project: 2017–2020

The purpose of the project is to estimate the distribution and species diversity of genus Sarcocystis parasites (Apicomplexa: Sarcocystidae) in Lithuanian Cervidae and cattle. Some Sarcocystis species are pathogenic to humans as well as to domestic and wild animals. Humans can get infected with Sarcocystis parasites when they consume undercooked beef or bacon meat; however, we cannot reject a possibility that infection from Carvidae meat is also possible. The species composition, distribution, host specificity and intra-specific diversity of Sarcocystis parasites in Cervidae have not been investigated in detail. The rate of cattle infestation with Sarcocystis cysts is recorded to be high (~90%) in Lithuania; however, species diversity of parasites from cattle has not been investigated in Lithuania so far. The projected morphological and molecular investigations will allow comparing the parameters of Sarcocystis infection in roe deer, red deer and elk naturally distributed in Lithuania with Sarcocystis infection in sika deer and fallow deer raised in farms; phylogenetic affiliation of Sarcocystis spp. detected in Cervidae with species pathogenic to humans will be examined; the species new to science will be described; new data about species composition, distribution, abundance and intermediate host specificity of Sarcocystis parasites from Cervidae will be collected; regularities of intra-specific genetic variability will be developed; attempts will be made to develop a relatively cheap, quick, accurate and molecular-investigation-based method for identification of Sarcocystis  species in cattle meat; as well as species distribution of these parasites in Lithuanian cattle will be evaluated.

The role of bacteriophages in regulating nitrogen cycling in cyanobacteria: from cell to community

Projects leader: dr. Sigitas Šulčius

Terms of the project: 2017–2020

Filamentous cyanobacteria play an important role in nitrogen cycling in the Baltic Sea, and it is expected that the viruses infecting these cyanobacteria could impact these processes as well. However, surprisingly little attention has been given to understanding how viral infections impact nitrogen fixation and its release in diazotrophic cyanobacteria. Moreover, no quantitative assessment of the diazotrophic nitrogen transfer mediated by viral infections and lysis to the microbial food web is currently available. The lack of this knowledge precludes our understanding of the food web and cyanobacteria bloom dynamics and prevents our ability to develop reliable ecosystem models guiding nutrient management. This project will therefore aim to evaluate the role of virus infection and lysis on nitrogen metabolism in cyanobacteria and to quantify trophic links and secondary production derived from virus-mediated nitrogen release. This will be done through culture-based laboratory experiments using targeted transcriptomic and metabolomic analyses in combination with stable isotope tracers and analytical chemistry. The results of the project will provide insights into how virus-mediated changes at cell (e.g. regulation of gene expression levels) and population (e.g. growth restriction and lysis) levels shape the ecologically relevant traits (e.g. N2-fixation, N-release and production of non-ribosomal peptides) of filamentous cyanobacteria in the Baltic Sea, and therefore ecosystem functioning and productivity.

Identification of natural blood parasite vectors

Projects leader: dr. Rasa Bernotienė

Terms of the project: 2017–2020

Avian blood parasites (Haemosporida and Trypanosomatida) are diverse, cosmopolitan, prevalent in Europe, and often cause diseases in birds. Despite of marked relevance of vector-borne diseases for animal health, vectors of avian haematozoa have been insufficiently studied. Sensitive PCR-based diagnostic speeds determining of significant links between parasites and blood-sucking insects, and is helpful in vector research. However, this tool alone does not distinguish between invasive and non-invasive parasite stages. Observation of invasive stages is needed to prove if PCR-positive insects can transmit infections. The main idea of this project is to determine natural vectors of widespread lineages of avian haematozoa and the host-parasite interactions at vector stage by close combining of traditional (microscopy) and molecular (PCR) diagnostic tools.

Defining taxonomic identity, ecology and distribution of fungi in coniferous forests

Projects leader: dr. Jurga Motiejūnaitė

Terms of the project: 2017–2020

The aim of the project is to determine the structure of the mycobiota characteristic of coniferous forests by combined morphological, ecological and molecular methods (including specimen-based molecular identification (barcoding) and next gen sequencing) and to define identity, distribution and functional traits of fungal species of different ecological and trophic groups. The results of the project will present a more exact pattern of mycobiota structure in coniferous forests which are especially important in Lithuania, both ecologically and economically. The project will considerably add  to the knowledge crucial to biodiversity conservation and  halting its loss (especially data on rare and protected species), as well as to forest management and disease control (data on tree endophytes and pathogens). The project results will supplement general knowledge in mycology by defining identity, taxonomic position and phylogenetic relationships of the less-known species and by addition of voucher-based data on fungi. Metagenomic studies will reveal fungal diversity in soils of pine stands following age, management intensity and climatic gradient.