research activities

Research activities of our laboratory concentrate mainly on RNA metabolism. The main objects of our studies are plants, with the emphasis on a model plant Arabidopsis thaliana. However, frequently our research observations from the model plant are transferred to crop plants, such as potato and barley. In our evolutionary studies on RNA metabolism we focus on liverworts, the oldest land plants, and it is mainly Pellia endiviifolia species.

We study mRNA and microRNA biogenesis and the involvement of different proteins in these processes. Primarily, the splicing events in pre-mRNA and pri-miRNAs are investigated, with special attention paid to alternative splicing (AS) events that are generally poorly recognized in plants. It is known, however, that in humans proper regulation of alternative splicing is crucial for the human health and development. We investigate whether AS of plant pre-mRNA and pri-miRNA is also crucial for plant development. We study the role of various proteins in mRNA maturation. Especially, we are interested in the role of CBP20, CBP80 , and SERRATE proteins in pre-mRNA splicing. Additionally, we study micro RNA biogenesis and the involvement of a protein complex consisting of the following proteins: HYL1 (DRB1), SERRATE, CBP20, CBP80, DDL, DCL1 . The role of other proteins in micro RNA biogenesis is also under investigation. These are: RDR1, RDR2, RDR6, DRB2, DRB3, DRB4, DRB5 . Using microscopic techniques, such as BiFC and FRET we investigate protein-protein interactions and their role in micro RNA biogenesis. We determine protein domains and inspect their capacity for reciprocal interactions during protein complex formation.

We are also interested in the effect of chromatin structure on RNA polymerase II transcription rates and its influence on splicing. We employ various A.thaliana mutants with disrupted histone genes, ChIP technique with the use of RNA Pol II antibodies, and qRT-PCR for splicing event analyses.

RNA metabolism responds to various abiotic stresses. We analyze RNA splicing and alternative splicing profiles in response to environmental changes. We designed and created a high throughput platform called miREX, (http://comgen.pl/mirex), to perform parallel analyses of all Arabidopsis miRNA precursor levels. We compare the influence of various abiotic stresses on pri-miRNA accumulation, as well as the significance of mutations in the genes encoding proteins involved in miRNA biogenesis.

One of the most important environmental conditions for Poland is water shortage and spring/summer drought threat. Abscisic acid (ABA) is a key regulator of plant response to drought. Our studies allowed identification of several proteins engaged in RNA metabolism and in response to drought stress. We make efforts to apply our findings to crop plants, such as barley, where we analyze the role of micro RNAs to drought and potato, and obtained plants with increased tolerance to water shortage. In these studies we used artificial micro RNAs and RNAi approaches to silence the activity of selected potato genes.

Another focus of our studies is the analysis of the liverwort P.endiviifolia microtranscriptome and identification of its genes involved in antheridia and archegonia formation. P.endiviifolia is a dioecious species what facilitates the dissection of genes involved in male and female gametogenesis. We identified new genes involved in male and female sex organ formation using cDNA-RDA/PCR technique. Currently, we study another bryophyte species moss Physcomitrella patens. It is relatively easy to knock-down or introduce new genes using homologous recombination in this species. We will inactivate moss orthologous genes identified in P.endiviifolia and observe the development of antheridia and archegonia in mutant plants.